IronStack

Privacy.

What the app keeps, what leaves your phone, and how to make it all go away. Your training log is yours. Here is everything else.

Effective October 21, 2026 · Mission Built LLC · Pittsburgh, PA

Mission Built LLC was formed on October 15, 2026. Nothing about what we collect, where it goes, how long we keep it or what you can ask us for changed.

Account to log

None

Your training log

On your phone

Leaves the phone

Stack AI questions. Cards you share. Workouts for a coach you link. Your live workout, to a board you pair. A workout your coach logs for you comes to your phone from theirs.

Sold or advertised

Never

Who this is

Mission Built makes IronStack. This page is the whole policy.

IronStack is made by Mission Built LLC ("Mission Built"), a Pennsylvania limited liability company in Pittsburgh, Pennsylvania. For the purposes of privacy law, Mission Built LLC is the controller of whatever this page says leaves your phone. There is no parent company, no subsidiary and no partner with access to your data. The app is not open source; this page is where to read what it does with your data, and the What the server holds screen shows you the rest, live.

No account to log

Logging never asks who you are.

You can log every set you will ever do without signing up, logging in or giving a name, an email address or a phone number. The only identity Stack AI's server ever sees is a key your phone creates in its secure hardware, which proves a request came from a real copy of IronStack and nothing more.

Social is the one exception, and it is optional. To share workouts with the people you train with, you sign in with Apple. IronStack asks Apple for neither your name nor your email, and stores neither if Apple sends them. The Social server keeps the stable, anonymous user id Apple gives it, and a sealed token it uses for one thing: disconnecting Sign in with Apple when you delete your account.

On your phone

Your training log lives in files on the phone.

Every set, workout, note and correction; your programs, workouts and exercises; your equipment, gear and home gym; your profile (sex, bodyweight, height, age); the details you give for a workout (bodyweight, sleep); your Stack AI chats; which library sections you show; and your Social settings. Changing or clearing a check-in hides the earlier answer; your log and its export keep it, like every correction, until you delete your data. All of it lives in files in the app's own container on your iPhone, written under the phone's encryption and protected until the first unlock after a restart. Those files are included in your iCloud or computer backup the way any app's data is; Mission Built has no access to your backups.

Apple Health, if you allow it. IronStack reads your weigh-ins, sleep, height, date of birth and biological sex, so the questions it asks before a workout answer themselves and Insights can line your sleep up with your lifting. It fills empty fields, and a bodyweight you took from Health stays current with your latest weigh-in when you open the app. A number you type yourself stays as you typed it, and you can always type over any of them. If you turn on the separate switch in Settings (off until you do), it saves each finished workout to Health as strength training. It never writes your weight or your sleep. Nothing from Health is used for marketing, advertising or anything but the log and your own Insights.

Apple Watch, if you wear it. IronStack on the watch is a remote for the workout on your phone. While a workout runs, the watch runs it as a strength workout, which is how it measures your heart rate and active energy. Your heart rate shows on the watch and, while the watch is in the workout, on your phone's clock; neither app keeps your heart rate or active energy. When the workout ends, and only if Save my workouts to Health is on, the watch saves it to Apple Health as one strength workout, with its heart rate and energy, and the phone doesn't save a second one. With the switch off, IronStack saves no workout, but the heart rate and active energy the watch measured during it stay in Apple Health, as Apple Watch does for any workout. A workout with nothing logged isn't saved, to Health or to your log; the readings the watch took during it stay in Apple Health, as with the switch off. The watch's heart rate and active energy never go into your training log. A workout file you import can carry heart rate and calories on a cardio set; those stay in your log and your export. IronStack never sends the watch's readings, or an imported file's heart rate and calories, to anyone: not to Stack AI, not to Social, not to a coach, not to a board. Once a workout or its readings are in Apple Health, your Health settings decide where they go. What the phone and watch tell each other (the workout on screen, the sets you log from your wrist, how it felt, your heart rate) goes over Apple's connection between your iPhone and your watch, never through Mission Built's servers. The watch keeps only what it needs to show the workout: the last screen the phone sent, a summary of your last finished workout, and any taps the phone hasn't received yet. Turn the watch off in Settings › Apple Watch and IronStack on the watch shows only that it's off. From your next workout it joins no workout, measures nothing and saves nothing, and the phone sends it nothing about your training.

Location, if you allow it. From your second workout on, the app asks once. During a workout it asks for roughly a kilometre of accuracy and rounds the coordinates to two decimal places the moment they arrive. The workout keeps the town name, those rounded coordinates, whether you were away from home, and the weather. To get the weather and the town name, the rounded point goes to Apple's WeatherKit and Apple Maps. Logging never needs location, and an export leaves coordinates out unless you switch them on.

Automatic travel, only if you turn it on. Set travel automatically, in Settings, is off until you turn it on. On, the app remembers where home is, rounded to about a kilometre, and watches for large moves in location (not a live track), even when a workout is not running, so it can switch you to Away when you are farther from home than the distance you pick (50 miles unless you change it) and back when you return. The check happens on the phone; no location is sent anywhere for it. Turning the switch off stops the watching; Forget home erases the home area.

Your voice, only while you hold the button. Speech is turned into text on the phone, by Apple's on-device speech recognition, only while you hold the talk button. No audio is kept or sent anywhere.

MealStack, if it is on the same phone. The two apps share a private shelf on your phone that only Mission Built apps can open. On it: the travel switch (Home or Away, which app flipped it, and your rounded home area if you use automatic travel); today's workout time when you move it, so the other app can offer to follow, Sync or Skip; and, only after you turn on each of two switches: Your last workout (when it started and how long it ran) and When you usually train (what time you usually start, by weekday, and how long your last 8 workouts ran, read out of this phone's log; MealStack uses them to work out when your workout will likely end and to place your after-workout meal after it). If you turned When you usually train on before it included workout lengths, IronStack asks again with one tap. Until you say yes, it shares your start times as before and no lengths. Each app also leaves a note that it is installed and when it was last used, which is how the Double Stacked badges know you used both. Neither app moves anything in the other without asking, and nothing crosses to a server to do this. Turn a share off and IronStack takes it back off the shelf.

This section also serves as the consumer health data notice some states require. The health data involved: bodyweight, sleep, height, date of birth and biological sex read from Apple Health with your permission; heart rate and active energy your Apple Watch measures during a workout, with your permission, which stay in Apple Health; the workouts written to Apple Health with your permission; and the sets, effort ratings and notes you log. Source: you, Apple Health, your Apple Watch, and a coach you link if they log a workout for you. Purpose: the log, your Insights, showing your heart rate during a workout, saving the workout to Health, and Stack AI when you turn it on and ask it. Shared with: nobody, except what goes to Anthropic for Stack AI, only after you turn Stack AI on and then only when you ask it something; the workout card you choose to share on Social; and, only if you link a coach, your workouts, plus the notes, sleep and bodyweight you choose on the consent screen, sent to that coach (and through The read, to Anthropic), as described next; and, only if you pair with a MissionStack board, your live workout's sets and effort ratings, shown on that board over the local Wi-Fi (see Your workout on a board). IronStack never sends your heart rate or active energy to anyone.

Consent and withdrawal. Nothing in this notice is read or shared until you allow it: Health access in iOS Settings › Health › Data Access & Devices, and Stack AI only after you turn it on, and then only when you ask. Stack AI is off until you turn it on from its permission screen; Settings › Stack AI turns it off. Coach mode shares nothing until you accept a coach's request on its consent screen; ending the link withdraws it and deletes the coach's copy on the server. Turning off "Your coach can log a workout for you" in Coach mode stops new ones from arriving, and our server deletes any already waiting, so it never reaches your history. A board gets nothing until you pair with it; Forget boards in Settings › Board withdraws it. Turning any of these off withdraws your consent from then on. Delete all IronStack data removes what is on your phone, what the Stack AI server holds and your Social account; the count-and-cost record of Stack AI use expires in about ninety days, what Anthropic already received follows its terms above, the Stack AI server keeps a short note for a day and one counter with no end date (see How long), and server backups drop deleted data within 30 days. Your rights under Washington's My Health My Data Act and similar laws (to confirm, access, delete and withdraw consent) are the ones in Your rights below, at the same address. Mission Built does not sell consumer health data.

What leaves your phone

Only what you use, and only when you use it.

Stack AI

Off until you turn it on. Then only when you ask.

Stack AI is off until you turn it on. The first time you open it, the app shows a permission screen that says what goes to Anthropic, asks you to confirm you are 18 or older, and asks first. Nothing goes to Anthropic until you turn Stack AI on, and then only when you ask it something. Turn it off any time in Settings › Stack AI; off, it sends nothing.

Off, the chat still answers a few questions from your phone alone (a lift's best, how often or when you last did it, what you did on a day or this week, plate math and swaps), and nothing leaves the phone for them. A question it can't answer there stays on your phone, unsent, while the permission screen asks: Turn on sends it, Not now gives it back to you unsent. Questions the phone answered aren't sent to Stack AI with later ones.

Sent to Anthropic, only when you ask:

Your question and this chat
Your last 90 days of training (or your most recent 90 days, if you've had a break) and today's workout: sets, weights, reps, RPE and notes
A summary of your whole log, worked out on your phone: for each lift, how often and when you've done it, and your bests. No notes.
The bodyweight and sleep you logged, typed in or from Apple Health
Where you are in your program, including a meet date
Photos (up to 5) with location removed, and PDFs and files you attach, with their names

Never sent: your name, email, Apple ID, location, contacts or your equipment and gear lists. Stack AI never sees anything from Social.

It goes to Mission Built's server at ironstack-ai.missionbuilt.io (earlier builds use ironstack-coach.missionbuilt.io until they update; it is the same server code), which runs on Cloudflare. The server passes it to Anthropic's Claude model, checks every weight the model names against a ceiling from your own sets, and sends the answer back.

What happens to it. Anthropic deletes it within 30 days and doesn't train its models on it. It keeps it longer (up to 2 years) only if a request is flagged for breaking its usage policy. Mission Built keeps a cost count for your phone, never what you said. An answer is held for 10 minutes in case your connection drops, then deleted. Your chats stay on your phone until you delete them; they are not synced anywhere. Stack AI can be wrong. It isn't medical advice.

To run Stack AI without accounts, the server keeps one small device record per install, for the allowance: the App Attest key id and the public half of the key your phone created, the receipt Apple issued for it, when it registered and was last seen, and how many Stack AI requests that install has made today and this month and roughly what they cost. It identifies the install, not you, and never holds your name. The record goes on its own about 400 days after your phone last reached the server.

Social

The cards you choose to share, to people you invite.

If you sign in to Social, the Social server at social.missionbuilt.io (on Cloudflare) holds your handle, your spotters and invitations, the workout cards you share, the support you give and get, who you have muted or blocked, reports you file, and a notification token so a new spotter or support can reach your phone. Notifications are asked for only when you have something to be notified about.

A card carries no messages and no comments. It holds the date and start time, how long you trained, how many working sets, the lifts by name from the app's list, the day's best moments, up to three badges, a title if you type one (up to 30 characters), and a place: your home gym as a phrase you pick, or the city name. Never coordinates. Your handle, a title and a city name go through a word filter on the server before they are accepted. Weights are left off unless you turn them on. You approve every card before it goes, and only your spotters, people you invited or who invited you, can see it. Anyone you send an invite link to sees your handle on it. You can take a card back at any time.

You can report a handle, a card title or a person, and block anyone, at any time. Reports use a fixed list of reasons (an offensive name or title, harassment, spam, impersonation, or something else), and the person reported is not told who reported them. Reports about a handle or a card's name are reviewed with help from Anthropic's Claude: the reported words (a handle or a card's title, up to 60 characters) are sent to Anthropic for a first look before a person decides. Nothing else goes with them: not your training log, not the card, not who reported it. Other reports go to a person only. A person at Mission Built decides every report before anything lasting happens, and can hide a card, reset or release a handle, or suspend an account. If you think a decision was wrong, email the address below.

Coach mode: only if you link a coach

Coach mode is for training with a real person, a coach who also uses IronStack. It uses your Social sign-in and does nothing until you and a coach link up, by their invite or yours, and you say yes. You can have one coach at a time, and being someone's spotter has nothing to do with coaching them.

You choose what your coach sees before anything is sent. Accepting shares every set (always, since that is the point) and your notes and how you felt; your sleep and bodyweight and your MealStack fueling summary are off unless you turn them on under Customize (see MealStack privacy). You choose how far back: from today (the default), 30, 60 or 90 days, or all your history (earlier versions offer 12 weeks). You can change all of this later in Settings › Coach mode. The app filters each workout on your phone before it leaves, and the server strips anything outside your choice again.

Where it goes. When a workout ends, it is sent to Mission Built's Social server at social.missionbuilt.io, on Cloudflare, stored in its database, and passed to your coach's phone. If you share your notes, the server checks them for words like “pain” or “tweak” so it can tell your coach a workout needs a look. We don't use your shared workouts for anything else, and we don't sell them. Edits and deletes follow. Plans your coach sends you, and the short note with them, come the same way, and stay suggestions until you accept them. Coach mode may send you or your coach a notification, through Apple, never between 9 PM and 7 AM unless you change the quiet hours.

A workout your coach logs for you. Your coach can log a workout for you on their phone, for example when you train together. When they finish, it goes to Mission Built's Social server and waits there until your phone fetches it, at most 14 days, and the server deletes it within 6 hours after that. Until it reaches our server it waits on your coach's phone; once the server has it, their phone keeps no copy. It lands in your history marked "Logged by @coach" and then follows your sharing choices like any workout. You can delete it: it comes off your history, and if you shared it, its card comes down; your log and its export keep it, like every correction, until you delete your data. It is never written to Apple Health or sent to MealStack. It never carries sleep, bodyweight, fueling, heart rate or location. The server keeps a short record (who, which day, delivered or not) for 30 days, deleted within 6 hours after that, so your coach can see whether it arrived. You can turn this off in Coach mode.

The read. Your coach can ask Stack AI to sum up a week of your training, this week or an earlier one. That sends Anthropic your handle, the week's shared workouts (seven days, at most 21 workouts) and a few figures your coach's phone works out from everything you've shared: how each lift's estimated max has moved, which lifts have stalled, and, if you share sleep, how hard your sets felt after nights under 7 hours. Your plan isn't sent, only where the week differed from it. The request comes from your coach's phone and runs on your coach's Stack AI allowance. Mission Built's server passes it on and keeps none of it; Anthropic treats it like any Stack AI request (see the table above). You can't turn The read off; ending the link stops it.

Ending it. Either of you can end the link at any time. Ending it, blocking each other, or deleting either Social account deletes your coach's copy on the server (the workouts and the plans), and your coach's phone deletes its copy as soon as it sees the link is gone. Until then, the server keeps each workout until the link ends or you delete that workout in the app. Server backups drop it within 30 days. Ending the link, blocking or deleting either account also deletes any workout your coach logged for you that hasn't reached your phone, and its record.

Sharing less later. If you share less later, the server deletes the workouts and details you stopped sharing from your coach's copy, and your coach's phone deletes them when it next checks in. Server backups drop them within 30 days. We can't take back what your coach already saw, or a week already summed up with Stack AI.

Coach notes. A coach can keep a private note about each lifter. It stays on the coach's phone (and in that phone's own backup), is never sent to us, the lifter or Stack AI, and is deleted when the link ends, on sign-out, or with Delete all.

Your workout on a board

If you pair with a MissionStack board, this iPhone sends it your live workout over the local Wi-Fi, encrypted, never through Mission Built: the workout and exercise names, your sets, planned and done, with weight, reps and RPE, the clock and when the workout started, your volume, your records as they happen, and the clock voice you picked. Never your heart rate, bodyweight, sleep, notes or name. It's on a screen the room can see. The board holds it in memory only and lets it go when the workout clears. The pairing is kept only on this iPhone, not in iCloud Keychain, and never moves to a new phone. Delete all or Forget boards (Settings › Board) forgets the board on this iPhone; to forget this iPhone on the board, use Forget this iPhone there.

The old log copy

Earlier builds had a switch, Copy my log to the server, off for new installs, that sent your raw log (including rounded location, bodyweight, sleep and notes) to storage Mission Built runs on Cloudflare, filed under a one-way hash of the install key. IronStack no longer offers it, and the Stack AI server takes no copy from any build, older ones included. Copies made by earlier versions were erased on October 5, 2026; nothing is copied any more. Settings › Stack AI › What the server holds (in earlier builds, Settings › Your data › Advanced › The server's copy) shows what the server keeps for your phone.

Nothing else

Notifications and the Home Screen widget are made on the phone from the same files the app reads. An exercise's Info (its demo videos, cues and muscle groups) comes with the app and sends nothing. For a lift without a demo, Search this lift opens a web search in your browser for the exercise's name (the way you typed it, for one you added), only when you tap it. Your search engine sees that search; Mission Built doesn't. No advertising identifiers, no third-party software kits in the app, no usage analytics sent to anyone, no tracking in Apple's sense of the word, no selling, no sharing for anyone else's marketing. The App Store privacy label says the same.

Who touches it

Three companies, each for its jobs.

Each of them is bound by its own terms and, where it processes data for Mission Built, by a data processing agreement, to protect your data at least as well as this page promises. None of them may use it for their own marketing.

WhoJobWhat they seeWhere

Cloudflare Runs the Stack AI and Social servers Sees each Stack AI request in transit. Stores the device record and allowance counters for Stack AI (and, after a delete, a short note for a day and one counter), an answer for 10 minutes in case your connection drops, the Social account and everything Social holds (including what Coach mode sends your coach and any workout your coach logs for you, in its D1 database). Keeps a count-and-cost record of Stack AI use for about ninety days. Global edge, US account

Anthropic Runs the Claude model behind Stack AI, and gives Social reports about a name a first look Receives what the app sends when you ask Stack AI something, after you turn Stack AI on, and produces the answer. If you have a coach, receives a week of your shared workouts, your handle, and figures your coach's phone works out from your earlier shared workouts, when your coach asks Stack AI for The read. For Social moderation, receives the reported words when a handle or a card's title is reported (up to 60 characters), for a first look before a person decides. Deletes it within 30 days and does not train its models on it; keeps it longer (up to 2 years) only if a request is flagged for breaking its usage policy. Stack AI is an AI and can be wrong; it isn't medical advice. Handles it under its commercial terms and Data Processing Addendum. United States

Apple Health, Apple Watch, Sign in with Apple, notifications, weather, maps, TestFlight, the App Store Health holds what you allow the app to read and the workouts it writes, including a workout your Apple Watch saves with its heart rate and energy. Apple's connection between your iPhone and your watch carries what the two show each other. Sign in with Apple identifies your Social account. Push notifications for Social and Coach mode go through Apple. WeatherKit and Apple Maps receive a rounded location to return the weather and a town name. Now and then the app may show Apple's own rating prompt; it never asks in a test build. A rating or review goes to Apple under Apple's terms. A written review is public on the App Store, where Mission Built can read it and reply. The phone keeps only the date and app version of the last ask, and Delete all removes it. Apple's own privacy terms cover these. Per Apple

How long

What is kept, and for how long.

Your training log, plan, notes, equipment and gear, profile On your phone until you delete them or delete the app. Included in your iPhone backup like any other app data.

Your Stack AI chats On your phone until you delete them. Not synced anywhere.

On your Apple Watch: the workout on screen, your last finished workout, taps waiting for the phone On the watch. Each is replaced by the next one the phone sends; a tap is gone once the phone has it. Removed by Delete all IronStack data, or when you delete IronStack from the watch.

Your heart rate and active energy during a workout Not kept by IronStack. During a workout the last reading is shown, dimmed once it is more than ten seconds old and marked lost after a minute, and it is gone when the workout ends; active energy is not shown. The workout the watch saves to Health keeps both there until you delete it in the Health app. With Save my workouts to Health off, the readings taken during the workout still stay in Health.

What you send Stack AI, including photos and files Mission Built never keeps what you said. The answer is held on the server for 10 minutes in case your connection drops, then deleted. Anthropic deletes what you sent within 30 days and doesn't train its models on it. It keeps it longer (up to 2 years) only if a request is flagged for breaking its usage policy.

The Stack AI device record (App Attest key id, public key, receipt, timestamps) Deleted when you delete your data in the app, or on request. Otherwise it goes on its own about 400 days after your phone last reached the Stack AI server. After a delete, the server keeps a short note for one day: the key id, when the record was made and deleted, and how many entries of an old log copy were erased. Nothing you sent. If a request your phone sent just before the delete arrives late, the note lets the server remove what it left, then the note is cleared. One number stays under the key id with no end date: a counter of your phone's requests, so an old one can't be sent again.

Stack AI allowance counters Today's and this month's counts. Nothing resets them on a schedule. Last month's counts are replaced the first time your phone asks Stack AI in a new month. If it never asks again, they stay until you delete your data in the app, or with no end date if the app is gone.

Count-and-cost record of Stack AI use (Cloudflare) One line per Stack AI question: when, which model, how many tokens, roughly what it cost, filed under a one-way hash of the install key. No question, answer or training data. About ninety days, then gone.

Daily totals for the whole app (Mission Built) How many Stack AI requests there were in a day, the tokens, the cost and the refusals, added up for everyone with no install key. Kept by Mission Built for its accounts, with no end date.

Social account, handle, spotters, shared cards, support given Until you delete your Social account or all your data in the app. Your sign-in on the phone lasts 180 days; an unused invite link expires after 7. Server backups drop deleted data within 30 days.

Coach mode: the link, the scope you chose, the workouts sent to your coach, your coach's plans and notification settings On the server until the link ends, from either side, or you delete the workout in the app. Ending the link, blocking either way, or deleting either Social account deletes the coach's copy on the server, and your coach's phone deletes its copy when it sees the link has ended. Server backups drop it within 30 days.

A workout your coach logged for you On the server until your phone fetches it, at most 14 days; a record of whether it arrived (no workout) for 30 days. Each is deleted within 6 hours after its limit. Ending the link, blocking either way, or deleting either Social account deletes both at once. Server backups drop it within 30 days.

A board's pairing (an id and a key; nothing about you) In this iPhone's Keychain only: not in iCloud Keychain, not in Export, never on a new phone. Until you choose Forget boards in Settings › Board, or Delete all IronStack data. Deleting IronStack leaves it in the Keychain, as iOS does; installing IronStack again forgets it. The board keeps its side until you choose Forget this iPhone there. The workout you send a board is held there in memory only, until the workout clears.

Notification token (Social) Until you sign out of Social or delete it.

Reports you file Until the report is closed, then up to one year for moderation. If you delete your Social account, they stay, with your account removed from them.

Reports about you, and moderation decisions Until the report is closed, then up to one year. If you delete your Social account, the text quoted from you is removed from them.

A log copy made before the app stopped offering it (only if you had turned it on) Every copy made by earlier versions was erased on October 5, 2026. Nothing is copied any more.

Seeing, taking and deleting your data

It is all in Settings. No email needed.

Settings › Your data › Export all my data writes every workout you have ever logged, your plan and your own exercises into one file, in the Mission Built Schema, a documented format you can read anywhere or bring back into IronStack. Export the raw log gives you the log itself, line for line.

Settings › Stack AI › What the server holds (in earlier builds, Settings › Your data › Advanced › The server's copy) asks the Stack AI server, live, for everything it keeps for your install and shows it to you. Forget this install on the server, on the same screen, erases it. The request is signed by your phone's key, so the server can only ever answer for the install that asked.

Delete all IronStack data is one screen that erases everything, everywhere, in order: first what the Stack AI server holds (the device record, the allowance counters, and any old log copy), then your Social account if you have one (which ends any coach link and deletes the coach's copy on the server), then everything on the phone. It reports each one. What the server keeps for a day after that is under How long. If the server or Social cannot be reached, it stops before touching the phone and says so, so nothing is left behind that you can no longer ask to erase; you can try again or delete the phone's data anyway. Social › Delete Social account deletes only the Social side: your handle, spotters, shared cards and support, and disconnects Sign in with Apple, and ends any coach link along with the coach's copy. Your log is not touched. Ending a coach link in the app ends just the link and deletes the coach's copy. Server backups drop what is deleted within 30 days.

Four things those buttons do not remove: workouts IronStack wrote to Apple Health, from your phone or your watch, stay in Health, where you can delete them in the Health app; the count-and-cost record of Stack AI use expires on its own within about ninety days; the Stack AI server keeps a short note for a day after a delete, and one counter with no end date (see How long); and a MissionStack board you paired keeps this iPhone until you choose Forget this iPhone on the board. Turning Stack AI off in Settings › Stack AI stops it from sending anything from then on; signing out of Social stops notifications.

If the app was deleted before you asked, nothing on the Stack AI server can be matched to you, which also means nothing there can identify you. The device record goes on its own about 400 days after that phone last reached the server. For that, for your Social account, or for anything else about your data, email support@missionbuilt.io. Mission Built will confirm within ten days and finish within thirty.

Your rights

Wherever you are, the same answer.

You can ask what Mission Built holds that relates to your install or your Social account, ask for it to be corrected or deleted, ask for a copy, object to or restrict its use, and withdraw any consent you gave, all at the address above, and you will not be treated differently for asking. Under the GDPR, the legal bases are your explicit consent for anything involving health data (Stack AI, Apple Health, the old log copy, Coach mode), your consent for Social and location, and Mission Built's legitimate interest in running the Stack AI allowance, keeping Social safe and keeping the service from being abused. Mission Built has not appointed an EU or UK representative; write to the address above. If you are in the EU, the EEA or the UK you may also complain to your supervisory authority. Under California law, Mission Built does not sell or share personal information and has not done so in the past twelve months.

Mission Built operates from the United States and the companies above process data there, so anything that leaves your phone leaves your country if you are outside the US. Cloudflare and Anthropic each rely on recognised transfer mechanisms such as standard contractual clauses or the EU–US Data Privacy Framework for that.

Stack AI is not a clinician

Stack AI can be wrong, and it isn't medical advice. It gives general training information from your own log. It will not name a weight above a ceiling drawn from your own sets, it writes down a workout or program you send it, and builds one only when you ask, always as a card for you to check, and it points any question about pain, injury or a medical condition to a qualified person. Check with your physician before making decisions about your health, and treat what Stack AI says as a starting point, not an instruction.

Age

IronStack is for adults, 18 and over. It is not directed at anyone under 18 and does not knowingly collect anything from them. If you believe someone under 18 has used the app, email the address above and the device record and any Social account will be removed.

Changes

This page changes when the app does.

If what the app collects or shares changes, this page changes first, with a new effective date at the top. A change that widens what leaves your phone will be asked about in the app before it applies to you. Effective October 21, 2026.