The most Played and popular game Clash of Clans (COC) are ending the support for IOS and android that is below IOS 11 and android 5.0 that means the users that are using IOS 10 or below and android users that are using ktitak 4.4 or below will be unable to play the game anymore later this year
image source clashofclans.com
If you are using such device that are below than the requirements then that means you are not be able to play anymore so i would recommend you to update your device as soon as possible or download the latest version of android or IOS to make sure you can easily update your game