Your hardware should meet the minimum requirements, as I tested the app on a similar Samsung device. Since the app uses OpenGL ES 3.2, your phone should not be older than 5 years. If you have already tried the toaster settings, you will also find a low performance button in the main menu. This disables important rendering settings and should improve performance. If it works, I might try something in the next patch. To disable the low performance mode later you have to remove the hack and press auto settings.
FYI, the app is still in preview, which means some things are not working yet. By the end of the week there will be a patch that will fix the most important bugs.