iOS Specifics
Each generation iPod touch has a different latest iOS available for it. This is important because not all games and apps will run on older versions of iOS. Please research what games and apps will work for you before purchasing.
4th generation iPod touch: iOS 6.1.6
5th generation iPod touch: iOS 9.3.5
6th generation iPod touch: iOS 12.4.5
7th generation iPod touch: Newest iOS