Tusky & Trunks are the top-tier Android Mastodon apps, IMO. Neither support Sharkey, though. Megalodon & Moshidon are a very close second, and mostly just because of cosmetic preference by me. And these both support Sharkey. Android also has takesama which supports Sharkey/Misskey. While it's stylish, it's also missing basic stuff like a Settings menu and Notification support.