MAC?

I have a MacBook air mid 2012,2 GHz Dual-Core Intel Core i7, 8GB of ram, and 520 ssd and it runs like a beast I worry about getting anything newer because of the security and knowing my luck I would managed to lock myself out because I work on iPhones. I dont know it's possible but if it is I will figure out away. It is definitely a great model because it's in most peoples price range and up-to-date enough you don't have much to worry about. Because with everything else that is Mac the newer it is the more it's going to cost you.