The App is been build last time in 2015: PPSSPP | F-Droid - Free and Open Source Android App Repository
I cant find any discussion about this app here:
https://forum.f-droid.org/search?q=ppsspp
There is a report about not being updated from 2016: F-Droid version out of date
The releases are tagged correctly in the project: Releases · hrydgard/ppsspp · GitHub
There was a try to update it here, but the build process was using an outdated build (not gradle based) : Help: Updating ppsspp (#1030) · Issues · F-Droid / Data · GitLab
Would be great if the version is updated 