Tap the menu button, then tap “Apps and notifications.” If you're updating to Android 8.0 and above you'll see a new feature: “Enable apps, game, or media download.” Tap the menu button. Tap “Apps & Notifications” in the new screen. Tap “Apps and notifications” in the list-down. If there is no list-down, tap “Manage apps.” Scroll down, then tap “Install from outside app store.” If you can't see Apps and Notifications, tap “Uninstall any apps.” That will start the installation. There are a lot of ways to install apps on Android, but Google Play is the best place! This is the best app manager in Android. It's much easier to manage your apps. It is recommended and recommended by many people.