You can install AdGuard for Android only manually. For more details on Google Play's restrictive policy, check out our blog
Allow installing apps from unknown sources in your device settings. In Android 8 or higher: tap the downloaded AdGuard APK file and then Install. If installations from a browser are not allowed, you'll get a notification. In this notification, tap Settings → Allow from this source → Back → Install.
For Android 7: give the browser access to the repository. Then agree to download the APK format. Open the downloaded file and install AdGuard.
For Android 6: open Settings, then select Additional settings in System & Device. Switch on Unknown sources and press OK in the system warning window. (Please note that the path towards these settings may differ depending on the device).
For Android 5: open Settings, then select Security in the Personal section. Switch on Unknown sources and press OK in the system warning window.
You can now install the app on your device. You will see the request to save the downloaded file. Press OK.
When the download is complete, press Install in the installation dialogue. Wait for the installation to complete and press Done.
AdGuard is now installed on your device. To launch the app, press its icon in the list of installed apps.