I find the only app in F-droid very lacking, and the couple I tested from the PlayStore lacked many of the technically available controls you can see on IRDB, Global Cache, JP1, etc.
I am seriously surprised there is no open source Android IR remote app that can truly put everything to shame, given that the info is out there. I may contact a friend of mine for a new Android app...
No doubt, and there used to be an app called "all for one IR remote" or something like that that I can't find from a cursory skim.
It allowed programming of codes from your existing remotes and also the bonus of using a URI for a IR code which then meant you could fire them off with other apps.
Problem these days is the hardware that supports IR Blasters is controlled by the likes of Xiaomi, and the apps available to use said hardware is limited to in-built system apps :/