Anyway one thing is still very weird:
I have another application from May 2021. If I build an APK-file today, I can't install it on my smartphone with Android 13
BUT
if I use the APK-file of the same application, that was built on May 2021 - I can successfully install it on my smartphone with Android 13.
I can't understand it...
Someone may correct me, but as far as I know, nothing much, if at all, has changed permissions - wise between Android 11 & 13.
Is you wife's phone also a Samsung, and your son's phone from another manufacturer or different model ?
You are welcome to share either the aia project or apk (this not directly on the community) so some one can test...or you could PM an interested Power User with these.
Post a screenshot of this message.
Because previously App Inventor targeted SDK30 and since a short time SDK31...
Taifun
Yes, but ...
so post the aia and/or upload the APK to Google Drive and post the link.
Thank you for any advices!
I repeat:
I have got an old application AIA-file (created on May 2021), that works OK since that time. I have got also an old APK-file (of this application), that was created AT THE SAME TIME (May 2021). I CAN install this file (APK) on my smartphone with Android 13 without any problems...
BUT
If I build a new APK-file TODAY (of the same application, without making any changes!), I can't install it on my smartphone.
Sorry, but it looks, that there is some problem (?) at MIT App Inventor...
I'm sending a link to my Google Drive directory with three files. You can find there also a screenshot with error-message from my smartphone (polish): DELETED
PS
EDIT:
Probably the "PushNotification" extension caused my problem. I have deleted it and now I can install my APP on my smartphone.
Anyway, thank you for your advices and sorry for disturbing on your community!
Wonderful you solved your install issue.
What extension did you use to provide push notifications Gregor? Knowing this extension caused an issue may help the community advise others.
Try this one (on Android 12+):
I didn't delete anything, but added a few lines in the Manifest.
That is the extension (I'm not sure if it is bad, but after I've removed it, I could install the app):
Super!
Could you send me this app as AIA-file? I'm curious what have you changed...
I'm only amateur who is playing with electronics and simple programming.
The extension is compatible with Android 11 and not with Android 13 it appears. That is useful to know. Thanks for letting us know. 
So does it install / work on your test devices (Android 12+)?
As I said, I only added a few lines in the Manifest.
Steps:
(done in < 30 sec).
See also e.g. here:
SteveJG: The extension is compatible with Android 11 and not with Android 13 it appears. That is useful to know. Thanks for letting us know.
If you are right, why can I still install the old APP-file from May 2021 with the old "PushNotification" extension on my smartphone with Android 13 if the extension is no compatible with Android 13...?
Anke: You need to customize the Manifest; add this line: Btw, as far as I know also Material Design / icons require Android ≥ 5 / "Lollipop" (API 21).
Danke Anke und Grüsse aus Polen!
@sokol_osw see e.g. here:
https://community.appinventor.mit.edu/t/ai2-test-updated-for-sdk-31-android-12/62733/17?u=anke
(EDIT: only for Power Users)
Ich kann das Link nicht öffnen ("private").
I don't know. Perhaps because it is not necessary to have android:exported='true' declared for Android 11. Note Anke's " because
android:exported="true"
is not declared in the Manifest with the extensions used.
Any tip/hint if extension developers need to take care of this" in Androids lower than 12. "
It appears the third party developer's extension does not declare android:exported='true'.
MIT's older Companion might have provided the required manifest and the most recent Companion might not
Every APK file includes a target SDK specification and newer versions of Android (generally) try to respect the rules of the target SDK specified. Your app built in May 2021 would have target SDK 28 or SDK 30 most likely, but your app built today will target SDK 31. Therefore, extensions that followed the SDK 28 or 30 rules will not work when the app is recompiled to target SDK 31. You will need an updated copy of the extension that follows the new rules.
Google Play Store is implementing additional changes going forward as well that apps that target at least 2 years back will no longer show up for newer Android versions. Hopefully they won't enforce this on Android users as a whole as well.
8 posts were split to a new topic: App not installed as package appears to be invalid, TaifunNotificationListener extension
