If you've already tried closing out apps running in the background of your device, the next ting you can try is to let your game load fully first before you start tapping and playing. When you visit, you should try the same and let their Kingdom fully load first. Clearing your safari cache may help as well. If none of those are helping, please try storing items until your game seems to be running more smoothly.
Sorry to hear guys.
Please try the same thing as I suggested above to luke1100. If you've already stored some items and you're still experiencing issues playing on your Kingdom, you may need to store a few more items.