Please browse the repo here to see which apps are available: https://github.com/GhostWriters/DockSTARTer/tree/master/compose/.apps
If an app folder exists then it is available for x86_64. Inside the folder will be files for ARMHF and AARCH64 if they are supported. If ARMHF is present but AARCH64 is not it will fall back to using ARMHF.
You can see descriptions of each app in the GUI or in the main yml file for each app in the repository.