I made an Android app using Android studio, deployed and ran it directly by using my mobile running Oreo. It installed successfully. But later I tired to share the APK from my mobile to other mobiles. But none of them are able to Install it. However, if I build the APK and share the app-debug.apk to other mobiles. It Installs successfully.
I can't build APK and share app-debug.apk it everyone. I usually deploy it in my mobile, share APK(which used to work before)
Can anyone please help
Please excuse typos, I have typed from mobile.
There might be a signing issue. Is your app signed? The default signing is the debug signing. When you just build and deploy or run it on a connected device, it is signed by default as a debug sign.
If it is not uniquely signed, then running or installing on other devices might not be possible. Look at the app signing instruction and guide by Google, here, if you wish to distribute your app on other devices.
Another problem might be in the security authorization of other devices. Your device on which you are building has the developer options turned on. To run and install unsigned apps you'll need to activate the developer options in the device you want to run it on. Look at this link about Developer Options and how to turn it on.