Welcome to the Candy Crush Saga Community
Do you have a question or need help with your game? Ask the Community.
I guess you have a 4th generation iPod, although it should still be compatible, as it ages the chances of not being capable of running the latest game updates increases, and as a result they will often lag and cause issues such as you are facing, but there is hope
Follow the instructions on this page:
http://support.apple.com/en-us/HT201398
If that fails i'd recommend this, especially If you've had the iPod for a while :