custom rom with only selected apps and no play store I'd like to restrict my mobile usage to a few apps only (basically phone, contacts, camera, google photo, whatsapp) and disallow installation of new apps and especially remove all browsers from the phone.

Background: I'd like to use this android phone to "tune off" and be only available for the urgent things.

Now: is it possible to build a custom rom which only the selected apps? Or would it be easier to just root the phone and install the core apps such as play store and chrome?
Install/trim whatever apps you want, then kill PackageInstaller either by using apps like TitaniumBackup (freezing it) or by deleting it altogether.

Back up and have a try - I haven't tried it myself, but that's the trick some of my local forum members have been using for a while