Preventing crashes is the job of the developer. What’s being described is likely due to a coding issue within the app and possibly how data is configured.

If an app is removed along with the data, that would indicate a reinstall of the app generates fresh data so that data would be at the latest version of the Realm file. Quite possibly, older data exists and the migration may not be accounting for it.

For example, suppose your app originally stored a persons age as an Int. Then, in a later version it was changed to a String. If the migration doesn’t account for that, a later version of the app or file will cause the App to crash.

So, to assist, we would need to see a duplicatable section of code that causes the crash along with the parameters of how your app configured. You may also want to implement additional error handling to deal with crashes or provide more details about the nature of the crash.