I have an old deactivated HTC Droid incredible from Verizon. I decided I was going to use it as like an iTouch, and it works just fine -- but the Google Play Store has vanished both from the home screen and the "Manage Applications" list (when I first turned on the phone after deactivation not after using it for a while).
At first I was okay with that because I could just go download aptoide or some other third party store. But after I downloaded the apk for aptiode and checked the "Allow Installation from unknown sources" when I tapped it to install I got "Do you want to install this applicaion" and the permissions ect. so I clicked install and then suddenly the phone rebooted? It just showed me the HTC logo, then brought up the home screen. I've tried this with several apks and none of them work. It does not have a SIM card slot.