When we develop tools and apps for clients, we put them in a test environment to make sure they are working the way the specifications indicate. Occasionally we ask the client to take a look at the toolkit to gather their feedback and send them an invite to download the test app. This can cause alarm and confusion as your phone might start displaying warning messages and blocking installations. This is because the app is on our Enterprise App Store and not located in the Apple App Store or Google Play.

HARM YOUR DEVICE warning - this app will not harm your device, click OK to continue

UNTRUSTED ENTERPRISE DEVELOPER Warning - this is being displayed because you need to go into your device and change the settings to allow Chrome to install unknown apps.

As of Android 8.0, the method to install apps from unknown sources has changed. Instead of the previous method where you gave permission to download through any existing app on your phone, from now on you need to give permission to specific apps that are allowed to install from unknown sources.

To set these permissions, go to “Settings -> Apps & notifications -> Advanced -> Special app access -> Install unknown apps”.

Here, select the app (usually your internet browser) that you want to grant permission to install from unknown sources. Then once you’ve tapped it, tap “Allow from this source” to enable unknown sources for that specific app.

Anything older than Android 8.0, you can enable and disable the feature right from the settings panel.

1. Open the App Drawer on your Android device, and tap on the “Settings” icon. It will open the settings panel where you can change all the settings related to your device. Also, you can pull down the notification bar twice, and then tap on the gear icon to open the Settings menu.
2. When the Settings menu opens, scroll all the way down until you see an option saying “Security & fingerprint.” On the devices that do not have the fingerprint feature, you will only see the “Security” option. Tap on that option, and it will open the security settings menu for your device.
3. When the Security Settings menu launches, scroll down and you will see an option that says “Unknown sources.” This option is what controls whether apps from outside the Play Store should be allowed to install on your device. By default, the option is disabled. Turn the toggle next to the option to the ON position, and the feature will be enabled on your device.
4. You will get the following prompt before the feature can be enabled on your device. It mentions the risks involved with installing apps from unknown sources. Tap on “OK” to enable the feature.
5. The feature should now be enabled on your device, and you may now exit out of the settings menu.
6. Now, tap on any APK file downloaded from anywhere on your device, and you should see that it installs without any issues. As long as the feature for unknown sources is enabled on your device, you will be able to install APKs without any issues on the device.