The minimum requirements to play Clash of Beasts on Apple iPhone or iPad are:  
  • Model: iPhone 7, iPad 2017, or later   
  • Operating System: iOS 10.0.1 or later   
  • RAM: At least 2 GB   
  • Storage: 1.5 GB  
Anything below in terms of hardware specifications will likely be unable to run the game at optimal performance, or may not allow the app to run at all.