How is it possible to make an app which can not be uninstalled android

Question

I know this may not be possible. but I just found such an app. I can't uninstall the app, even not able to clear data, cache of the app an really this is not a system app. What this app does is just spam my phone with push notifications all time.

My Phone is not rooted!!

So my question is how is it possible to make such an app?

Solution 1

The apps which have administrative permissions, which can be found under Setting > Security & Private > Device Administrator, cannot be uninstalled without revoking administrative permission.

Solution 2

The only way to make your application uninstallable ( You can't really if the user is using a rooted phone) would be to install it directly in Android bundle, pushing it via ADB (while rooted) to the

/system/app

directory...

Then, it's in anyway possible for a dev with standard access to the users phone.