I don't know how many people don't do this when they uninstall apps, but everyone I know says they've never even heard of doing this, but before uninstalling apps, go into the device Settings, Apps, select the app from the list, then usually at the bottom, Force Stop or Force Close it, then scroll back up to Storage and click it, then click on Clear Data. You don't need to Clear the Cache since Clear Data automatically takes care of that. After that, it's ok to uninstall it.
Again...
Settings
Apps
Force Stop or Force Close
Storage
Clear Data
Uninstall
Following these quick, easy and painless steps are the only way to insure that there aren't any residual traces of the app left that are still infecting other apps and/or settings and still collecting info. I'm sure you can also boot into Recovery Mode and do a much deeper uninstall, but I haven't played around in recovery mode for several years and I've forgotten so much about it.