"Installed" in Google Play means that, at one time, using that Google account, you installed the app. If you uninstall it, get a new phone, grind the old phone into pebbles, the button will still say "Installed", it has nothing to do with the phone, just the Play site - you once installed the app.
If you don't have it on your phone, and tap or click the "Installed" button, the app will install. Only the text on it changes, the function doesn't. (Make sure, when you get the popup if you're using a web browser, that it's installing on the right phone - if you've had more than one on that account, it may default to installing it on an older one. [If you're using the Play app, that won't happen.])
03-15-2018 04:58 PM