that's the cost of publishing to AppStore and GPlay - if they were only on FDroid, they could've opened up some time ago.
Discussion
Or publish an app with the Nostr protocol, so you can use clients like nostr:npub10r8xl2njyepcw2zwv3a6dyufj4e4ajx86hz6v4ehu4gnpupxxp7stjt2p8