I downloaded retroarch through the website not with the google play store. There is now a new version. To update it do I have to uninstall the version I have and reinstall the new one? Or can I just use the online updater in settings? Thanks!
Just download the new version and sideload it the same way you did the previous one and it should update it.
Alright thanks just did that and it worked
For ongoing updates, you can use f-droid. There is an f-droid repository for RetroArch that will let you stay up-to-date.