I have release apk with signed keys but it's not installing on android devices, its shows this message "**The apk failed to install
Error: Could not parse error string"** but debugging mode apk, the app works fine.

release command

flutter build apk --release.

I did follow this [question](https://stackoverflow.com/questions/48054291/cant-build-release-apk-for-flutter?rq=1) to solve it, hope it helps someone.
['https://Stackoverflow.com/questions/56464704', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/6654129/']
If you're trying to install a signed APK after using a debugging mode APK, Android will detect differences in signature, and refuse to install it.

Make sure you've uninstalled the unsigned debugging APK first from the device, and try to install again.
Please check available disk space on the target Android Device before doing any actions.
For most of cases it is a due to insuffisant space on the device.