Bluetooth keyboard

Well I am thinking to buy a bluetooth keyboard mainly on using for playing a game called Roblox. I am not using it for typing and need to see if it works on Roblox before I spend $30. I see people do it but they use android. Not iOS. And people have said that iOS is not capable with Bluetooth keyboards when it comes to games such as Roblox, but capable only with android.

Please reply as I am making my decision very quickly.

Thanks