For old Android versions (4.0, Lollipop 5.0, Marshmallow 6.0, Nougat 7.0)
- Go to your Android Settings > Security
- Check the option Unknown sources
- Tap OK on the prompt message
- Select Trust
If you are running Android 9.0 and later, you will need to allow Unknown sources for each app willing to install an apk file. For instance if you are using two browsers such as Chrome and Firefox, you will need to allow both Chrome and Firefox to install unknown sources.
For New Android Versions (Oreo, Pie, Android 10, 11 and 12)
- Go to your Android Settings > Apps & Notifications
- Select Advanced or the three dots at the top-right corner – users might see either option depending on their device
- Select Special App Access
- Choose Install Unknown Apps
