The requirements to play the game

Heroes Defense is available for iOS v.12.0+ and Android 5.1+. The game will perform better with the device has more than 1GB RAM. Stable Internet connection is required to play the game. 

Make sure that you are connected to a steady Wi-Fi network. Keep in mind that if you are connected via mobile data (3G/4G) and the connection bars are full, it does not always guarantee a solid Internet connection. Networks can slow down or get overloaded at times, especially when you are playing in a moving vehicle or the network base station is too far away from your location.