Which VR should I buy that is under $100?

Purpose: I will be using the VR with my iPod touch 5 and hopefully my iPhone one day when I get it back. PC/Steam Compatibility is a major plus. Budget: Must be $100 or less Requirements: Must work for iPod touch generation 5 and higher and preferably PC/Steam compatible. I need something to look forward to and save up for. I appreciate your input!