Privacy.

MealStack 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.

MealStack has no sign-up, no login and no password. Nothing you do in the app is tied to your name, email address or phone number, because the app never asks for them. The only identity the server ever sees is a key your phone creates in its secure hardware, which proves a request came from a real copy of MealStack and nothing more.

Your plan, every day's log, the ingredients you add, the meals and stacks you save, your Stack AI chats, and what you enter in About you: bodyweight, height, age, sex if you chose to say, how you train, and your goal. All of it lives in files inside 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, each way behind its own switch. With Write the meals you log on, the app writes four numbers for each meal you log into Apple Health, at the time you ate: protein, carbohydrates, fat and calories. Correct or un-log the meal and the app takes those entries back out. With Read food and weight from other apps on, the app reads two things: the food other apps logged today (calories, protein, carbohydrates and fat, and which app logged them), shown beside your totals and never added to them; and your latest weight, read when the app opens and offered on Today and in About you when it is newer than the weight in About you and differs by half a kilo or more. It is never put into About you unless you tap Use it. If you tap Not now, the app keeps that one weigh-in (its weight and date) in a file on your phone so it isn't offered again. MealStack's own entries are left out of what it reads. What it reads stays on the phone. If you put your weight in About you, it goes to Anthropic with every Stack AI request, like everything else in About you, once you have turned Stack AI on. Nothing from Health is used for marketing, advertising or anything but these screens. Both switches are in Settings › Apple Health, and in the Health app.

Your calendar, only if you ask. Check my calendar is off until you turn it on. On, the app reads today's events on the phone so it can offer to move a meal that lands in one. It never changes your calendar, keeps the events only while the app is open, and never sends them anywhere, Stack AI included. If you accept a move, the new meal time is part of your plan like any other.

Location, only for automatic travel. Set travel automatically is off until you turn it on. On, the app asks for your location, remembers where home is, rounded to about a kilometre, and turns Travel on when the phone is more than 100 km from there and off when you are back. The home area and the check stay on the phone; no location is sent anywhere. Turning the switch off stops the watching; Forget home erases the home area.

IronStack, if it is on the same phone. The two apps share a private shelf on your phone that only Mission Built apps can open. MealStack puts there the travel switch (and your rounded home area if you use automatic travel), today's session time when you move it, and, with IronStack times my after-session meals on, the name and contents of the first thing after the session, so IronStack can call it when you finish. It reads the same from IronStack, and: when your last workout started and how long it ran, if you turned on Your last workout in IronStack; how long your last 8 workouts ran, if you said yes to When you usually train in IronStack after it began to include them (if you turned it on earlier, IronStack asks again); and a note that IronStack is installed and when it was last used, for the Double Stacked badges. MealStack uses those workout lengths to plan around a session as long as yours usually is. Until you say yes in IronStack, or while it has fewer than 3 of them, it uses the Usual session length you set in Settings, or 90 minutes. With IronStack times my after-session meals on, MealStack moves today's session to the time an IronStack workout actually started, once per workout, and says so on Today with Undo. Any other move one app makes is offered in the other, never made without asking, and nothing crosses to a server to do any of this.

Your fueling summary, for IronStack's Coach mode. On the same shelf, MealStack keeps a short summary of each of your last 120 days: how many meals went in on time (4 of 5), how many minutes early or late the meal before your session and the shake after it were, your protein, carbohydrates, fat and calories as a percentage of your target, and whether it was a recovery day. Beyond the names of those two meals as they appear on your day, no foods and no amounts. Only IronStack on the same phone can read it, and it stays on the phone unless you link a coach in IronStack and switch Fueling on in Coach mode (it is off until you do, when you accept a coach or later in Settings › Coach mode). Then IronStack sends it with your workouts to your coach through Mission Built's server, as IronStack's privacy page describes, and turning Fueling off later, or ending the link, deletes your coach's copy. Delete all MealStack data removes the summary from the shelf.

This section also serves as the consumer health data notice some states require. The health data involved: the four nutrition figures the app writes to Health with your permission; the food totals from other apps and the weight it reads from Health with your permission; the body measurements you enter in About you; and what you log. Source: you and Apple Health. Purpose: the log, the day, the target, 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, as described next; with barcode lookups on, the barcode number of a food you scan, to Mission Built's server and, if our server doesn't know it, to Open Food Facts; and your fueling summary, only if you switch Fueling on in IronStack's Coach mode, to the coach you linked there.

Consent and withdrawal. Nothing in this notice is read or shared until you allow it: the Health switches in Settings › Apple Health, 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. Turning either off withdraws your consent from then on. Barcode lookups follow the same Stack AI switch. Delete all MealStack data removes the foods you saved from a barcode, and what is on your phone, the entries it wrote to Health, and the server's device record and counters, apart from the one request counter above (if the phone is offline, the next time it opens with a connection); usage data and the accounting record of Stack AI use expire in about ninety days, and the server's barcode lookup count expires on its own within two 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.

Settings › Stack AI › What the server holds asks the server, live, for everything it keeps for your install and shows it to you, with a share button. The request is signed by your phone's key, so the server can only ever answer for the install that asked.

Settings › Start over › Delete all MealStack data does the whole job in one tap: it tells the server to delete the install's device record and its allowance counters (usage events can't be deleted one install at a time: they hold only a hash of the install's key and expire in about ninety days), then removes every file on the phone, the entries this app wrote to Health (and blanks MealStack on your Apple Watch the next time it hears from your iPhone), your answer to the usage question, and the install's key. If the phone is offline at that moment, the phone is still wiped and the server's record is deleted the next time the app opens with a connection. If the server can't confirm the install, the key is dropped and the record expires 400 days after it was last used. Turning off Send usage data in Settings withdraws that consent from then on; turning off Stack AI in Settings › Stack AI stops it from sending anything.

The one case a button cannot cover is an app that was deleted before asking: with the key gone, nothing on the server can be matched to you, which also means nothing on the server can identify you. If you want to ask anyway, or ask anything else about your data, email support@missionbuilt.io. Mission Built will confirm within ten days and finish within thirty.

The routes behind those two buttons are tested for isolation on every change to the server (an install can never read or delete another's) and probed every 6 hours in production by two synthetic installs; if a probe ever fails, both routes close until a person has looked.

You can ask what Mission Built holds that relates to your install, 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), your consent for the usage-data question, and Mission Built's legitimate interest in running the Stack AI allowance 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.

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