Why your AI-built app forgets data on refresh, and how to fix it
The six reasons an AI-generated app loses data when you refresh, switch devices or publish, how to tell which one you have in five minutes, and what to ask the AI to change.
Key Takeaways
- Gone on refresh means memory. The app only held the data in the open page. Nothing was written anywhere, so reloading wipes it.
- Gone on another device means browser storage. The data was saved in this browser only, often with localStorage. It survives a refresh but never reaches a server.
- Gone after publishing means two databases or none. Preview and live versions often use separate databases, or the live version isn’t connected to one at all.
- Gone after a while means the server’s memory. Serverless functions don’t keep files or variables between requests reliably. Data must go to a database.
- The fix is the same in every case. Store data in a database on a server, load it from there when the page opens, and check that saves succeed.
Quick-Start Prioritization Framework
| When does the data disappear? | Most likely cause | What to ask for |
|---|---|---|
| On refresh | Data kept only in page memory | Save each change to a server database and load it on page open |
| On another device or browser, but not on refresh | Saved to localStorage in the browser | Move storage from localStorage to a server database |
| After publishing | Live app not connected to a database, or separate preview and live databases | Connect the live app to its database; check the environment settings |
| Randomly, hours later | Data kept in a serverless function’s memory or files | Write to a database instead of variables or files |
| Never saved: the form clears but nothing appears | Save request failing, often blocked by a permission rule | Show save errors on screen; check the logs |
| Shows old data until you refresh | Caching, not data loss | Refresh the list after each save |
You asked an AI tool for an app, it looked perfect, you added a few records, and then you refreshed the page and they were gone. Or they survived the refresh but weren’t there on your phone. Or everything worked in the preview and the published version started empty. This is one of the most common problems with AI-generated apps, and it almost always means the app isn’t saving to a database on a server, or is saving somewhere you didn’t expect. This guide explains the causes in plain language, gives you quick tests to find yours, and tells you what to ask the AI to fix.
How saving is supposed to work
A web app has two halves. The frontend runs in the visitor’s browser and draws the screens. The backend runs on a server and talks to a database. When you click Save, the frontend should send the data to the backend, the backend should write it to the database, and the next time anyone opens the app, from any device, the frontend should ask the backend for the latest data.
AI tools are very good at the frontend, because that’s what you see and what you describe. If your request didn’t mention saving, or the tool doesn’t include a backend, the AI may build a convincing frontend that keeps data somewhere temporary. Each cause below is a different temporary place.
Cause 1: the data lives only in page memory
Frameworks like React keep what’s on screen in variables called state. Adding a record to state makes it appear instantly. But state belongs to that open page. Reload, and the page starts over from the code, which often contains a few hard-coded sample rows.
How to recognize it
Add a record, press refresh. If it’s gone and the same sample data reappears every time, this is the cause. Another clue: the app works with no internet connection after it has loaded, because it never talks to a server.
What to ask the AI
“Store these records in a database table on the server. When I add, edit or delete one, save the change to the database. When the page loads, fetch the records from the database. Remove the hard-coded sample data.”
Cause 2: the data is saved in the browser, not on a server
A common step up from memory is localStorage, a small storage area built into every browser. MDN’s documentation explains that localStorage data is saved across browser sessions and has no expiration time, which is why the app survives a refresh and even a restart. That makes it look like real saving.
Why it isn’t enough
localStorage belongs to one browser on one device, for one website origin. Your phone, your colleague’s laptop and a different browser on your own computer each see their own empty copy. MDN also notes that data from a private or incognito window is cleared when the last private tab closes.
It can also be deleted for you
Browsers may clear stored data. MDN’s page on storage quotas explains that by default storage is “best-effort” and can be evicted when a device runs low on space, and that Safari, with cross-site tracking prevention on, deletes script-created data for a site that hasn’t been interacted with in seven days of browser use. That is fine for remembering a theme preference and wrong for customer records.
How to recognize it and what to ask
Add a record, refresh (it stays), then open the app in a private window or on your phone (it’s missing). Ask: “Move all saved records from localStorage to a server database, keep localStorage only for display preferences, and migrate the records I already have.”
Cause 3: the published app isn’t connected to the database
Some tools build against a database in the editor but need extra setup for the live site, such as connection keys stored as environment variables in the hosting settings. If those are missing, the live app may fail to load data, show an empty list, or quietly fall back to sample data.
Separate preview and live databases
Many platforms deliberately give the preview and the live app different databases, so testing can’t damage real data. That’s good practice, but it surprises people: records you added in the preview don’t appear on the published site. Check your tool’s documentation for how it handles development and production data, and how to copy data between them if you need to.
What to ask
“The live app shows no data. Check that it’s connected to the production database, that the required environment variables are set in the hosting settings, and show me any errors from the live logs.”
Cause 4: the server keeps data in its own memory or files
Sometimes the AI does write a backend, but the backend stores records in a variable or a file on the server instead of a database. On a regular computer that might work. On modern serverless hosting it doesn’t, at least not reliably.
Why serverless forgets
Serverless functions run in short-lived environments that the host starts and stops as needed. AWS’s Lambda documentation, for example, says Lambda terminates execution environments every few hours even for busy functions, and that you “should not assume that the execution environment will persist indefinitely.” Several copies can also run at once, each with its own memory, so two users may see different data.
How to recognize it
Data survives refreshes and shows on other devices for a while, then disappears, or two people see different lists. Ask: “Replace any in-memory arrays or file storage on the server with a database table.”
Cause 5: the save is failing silently
Here the app does have a database, but the write never succeeds. The form clears, so it looks saved, but the request returned an error the screen didn’t show.
Permission rules blocking writes
Databases with per-row security rules refuse writes that no rule allows. Supabase’s documentation, for instance, describes Row Level Security as authorization rules that run inside the database. If a table has that security switched on but no policy permitting inserts by signed-in users, saves fail. That is the correct secure default; the fix is to add the right rule, not to switch security off.
Other common failures
A required column the form doesn’t fill, a date in the wrong format, the user’s session having expired, or the app saving to a table name that doesn’t exist.
What to ask
“When a save fails, show the error message on screen instead of clearing the form. Then check the server logs for the last failed save and fix the cause.”
Cause 6: it’s saved, but the screen shows an old copy
Not every disappearing act is data loss. Apps often cache lists to feel fast. If the list doesn’t refresh after a save, the new record seems missing until you reload, which is the opposite symptom of cause 1. Ask the AI to refresh or update the list after each successful save.
A five-minute test to run on any AI-built app
Run this before you trust an app with real data, and again after publishing.
- Add a distinctive record, such as “Test 1142”.
- Refresh the page. Still there? Memory is ruled out.
- Open the app in a private window and sign in. Still there? Browser storage is ruled out.
- Open it on your phone. Still there? It’s on a server.
- Ask a second test user to sign in. They should see it only if your permission rules say so.
- Publish, and repeat the steps on the live address.
Common mistakes when fixing it
The quick fixes people try often create a second problem.
Asking the AI to “make it save” without saying where
The quickest answer to that request is often localStorage. Say “in a database on the server” explicitly.
Switching security off to make saves work
Disabling row security or permission checks makes saving succeed and exposes every user’s data. Add a specific rule instead.
Forgetting existing data
When moving from browser storage to a database, records already saved in users’ browsers need a one-time migration, or they’re lost.
Testing only in the preview
The live app may use a different database and different settings. Always test the published version too.
If you’d rather start with a database built in
If you’d rather not wire this up yourself, AI app builders that include the backend avoid most of these causes from the start. Floot, for example, gives every app its own Postgres database and serverless endpoints, so records are saved on the server from the first version, and you can download the database at any time.
Frequently Asked Questions
Why does my app lose data when I refresh the page?
Because the data was only held in the page’s memory and never sent to a server. Reloading restarts the page from its code. The fix is to save each change to a database and load records from it when the page opens.
Is localStorage a database?
No. It’s a small storage area inside one browser on one device. Data in it doesn’t reach other devices or users and can be cleared by the browser or the user. It’s suitable for preferences, not business records.
Why does my data show in the preview but not in the published app?
Many platforms use separate databases for preview and live versions, or the live app is missing its database connection settings. Check your tool’s documentation on development and production data and look at the live logs.
Why did my data disappear hours later?
The backend may be storing data in server memory or temporary files. Serverless hosts start and stop environments; AWS’s Lambda documentation says environments are terminated every few hours. Store data in a database instead.
How can I check whether my app really saves to a database?
Add a record, then open the app in a private window and on another device. If it appears in both, it’s stored on a server. If it disappears, it was in page memory or browser storage.
What should I tell the AI to fix it?
Be specific: store records in a database table on the server, save every add, edit and delete there, fetch from it on page load, show errors when a save fails, and remove hard-coded sample data.
Sources
- MDN Web Docs, Window: localStorage property https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage
- MDN Web Docs, Storage quotas and eviction criteria https://developer.mozilla.org/en-US/docs/Web/API/Storage_API/Storage_quotas_and_eviction_criteria
- AWS, Understanding the Lambda execution environment lifecycle https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtime-environment.html
- Supabase, Row Level Security, 2026 https://supabase.com/docs/guides/database/postgres/row-level-security