Q:

Android Studio how to create working APK

I have an Android Studio Project and I need to create a runnable apk file for my beta testers (I pass the apk to them directly (via mail)).  I tryed both to build an unsigned APK and to generate a signed one.  But when I or my beta testers try to intall the APK, the installer say "App not intalled". 
How can I build an APK file which work? 
Thanks for help. 

A:

Having seen you case, you need to make sure that you are trying or installing signed apk.  I was facing the same issue of App not installed what I did to over come the issue I build signed apk.  And everything worked fine.  Although the version before 3.0, without signed apk used to work, but after 3.0 or above without signed apk(if you installed directly) will not work.  This will throw the same App not installed error.