If you are looking for a wireless gamepad for enjoying mobile games, especially for the MOBA(Multiplayer Online Battle Arena) games, the Flydigi and Gundam collaboration controller, Apex 2, would be a great choice.

It supports Android, the system under ios13.4, and PC. The XYB button can be moved in 360-degree, which suits the action in some games.
With 27 buttons equipped, it is obviously powerful enough to map every single button in the game like PUBG.