There are several operating systems being used, from 4.0 KitKat all the way up to 9.0 Pie. I have noticed some apps not working on certain operating systems. Each operating system will have bugs when it comes to certain applications. If a app does not work on your device, there's a chance it's because of the operating system you're running it on. Android 6.0, 7.1 and 8.1 seem to have the best overall compatibility with the majority of apps.
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