A quick, simple guide. It's easier than it looks, and you only do it once.
Three simple steps — and on some phones the warning doesn't appear at all.
When the download finishes, open the file (from the notification shade or your “Downloads” folder) and tap Install. On many phones the installation completes right here.
If you see the App blocked to protect your device dialog, tap the Install anyway button at the top of the dialog. You may need to tap “More” or “Details” first for the button to appear.
If you're asked to allow Install unknown apps, turn on the switch for the app you opened the file from (your browser or file manager), then go back and tap “Install” again. This permission only applies to that source, and you can turn it off later.
The same transparency you'll find in our Privacy & Trust Center.