I have a program working in the Android Emulator. Every now and again I have been creating a signed .apk and exporting it to my HTC Desire to test. It has all been fine.
On my latest exported .apk I get the error message 'App not installed' when I try to install the .apk. It runs fine on the emulators.
As I have mainly been testing on the emulators and only every now and again exporting to a real phone I am not sure when this happened. What is the likely cause of it not installing on a physical phone but running fine in the emulators?
I have tried rebooting the phone & removing the existing .apk, does not fix the fault.
For those who are using Android Studio 3.
Suryanarayana Reddy's Answer is correct thought it doesn't state steps to solve it, hence.
in your AndroidManifest.xml under the application tag add
testOnly="false"
andandroid:debuggable="true"
like so:Edit
then in AndroidStudio's menubar Build > Build APK(s)
for me the cause was that i had multiple builds using different build variants on same phone:
what happened was that some of these builds were built by me, another one was sent to me by another developer.. trying to install the developers while i had other builds (built by me) caused the above error.
so the fix was simple: delete all the builds on my phone (regardless of build variant).. then install the apk sent by my peer.. and it worked like a charm
I had a similar issue and it was because I was trying to install an apk on a phone with a previous version of the same apk, and both apks hadn't been signed with the same certificate. I mean when I used the same certificate I was able to overwrite the previous installation, but when I changed the certificate between versions, the installation was not possible. Are you using the same certificate?
My problem was: I used the Debug Apk, that was generated while I did the Run command from Android Studio
Solution was: Instead of using this file, clean project and click Build > Build APK(s) from Android Studio. Then you can use the generated APK from the usual folder (app/build/outputs/apk/debug/)
The file that was generated like this installed without a problem.
You also may encounter this issue because your device manufacturer did not license the Google commercial apps, such as Play Store, YouTube, Google Maps, etc. Follow this answer to solve the problem.
Clearly there are many causes of this problem. For me the situation was this: I had deployed to my nexus 7 (actual device) from within the Android Studio (v1.3.2). All worked fine. I then created a signed apk and uploaded to my Google Drive. After disconnecting my nexus from the usb, I went to the settings/apps and uninstalled my app (App1). I then opened google drive and clicked on my App1.apk and chose to install it (need to ensure you have allowed installation of apks in settings). Then I got the dreaded message "App not Installed"
Solution for me: go back into settings/apps and scroll though all apps and at the bottom was a pale version of my App1 (note the original App1 was at the top in Alphabetical order which was deleted as above). When clicking on the pale version it said "Not installed for this user". (I had set up my nexus to have more than one user). But in the top right corner there is a three dot button. I pressed this and it said "Uninstall for all users". Which I did and it fixed the problem. I was now able to click on App1.apk and it installed fine without the error.