Apk crash down at start and show nothing 😪

Hello everybody,
You are a great community and I am amazed at how easy yet effective you can create an app here.

Now I’ve invested quite a bit of time and rely on the preview and “live test” implementation. Everything works fine. Unfortunately, the awakening came after the first download of the apk file.

Unfortunately, the Android app does not start at all. A window is opened which, however, closes again in a fraction of a second.
This happens both on a newer smartphone with MIUI14 and on an older tablet.

I have already shortened the app to the login screen and another screen that checks which user is logging in. You will then be redirected to complete the registration data such as “Name” or, if this has already been done, you will go directly to the AppScreen.
Unfortunately, the app crashes even with this “simple” sequence.

I based my project on the “Sign In + Out by beaver-projects”.

  • The ID of the crash project is: 6426e44dcc9cd6541bf60079
  • A link to the apk: Strichliste
  • I have a Firebase login and Google Sheets for the spreadsheet functions needed for the app.

I am a beginner when it comes to app programming, but have experience with WordPress and html and php from the 2000s.
I hope it’s just a small rookie mistake and someone can help me with my problem…

Hello @staplerwerkstatt
Welcome to our community
Thank you for sharing all of these
We will check your app and will provide an update as soon as possible.

@staplerwerkstatt
I checked your project.

The issue is caused by some variables and especially the ones that have an invalid character like: #

In order to fix it, you will need to remove the variable.

All characters must be alphanumeric or an underscore [a-z, A-Z, 0-9, _]

Below is the invalid variable that I found

image