Constraints are a good thing, especially when it comes to design. The challenge of working within certain restrictions forces you to be creative and come up with clever solutions to problems you simply don't encounter when you have complete freedom.
Icons are one area in particular where people's creativity within very specific (and small) constraints never ceases to amaze me. So much information and feeling can be conveyed using a small symbol and subtle details. I love to explore and see how different designers approach certain concepts, and recently I found myself at the intersection of vintage nostalgia and the iOS icon. It's an intersection where old meets new in really cool and inventive ways, and there are a ton of great designers having fun with this retro-contemporary concept.
Below is a collection of awesome vintage iOS icons for your inspiration.
As you've probably noticed, vintage music players of all varieties are a recurring theme when it comes to icons. I would imagine that's because all those intricate little details are as much fun to design as they are to look at. In fact, all of these designs have such great detail it makes you want to grab whatever gadget is depicted and play around with it.
Now if you'll excuse me, I'm off to listen to some vinyl while I play my Nintendo.