Buying an unlocked iPhone makes it cheaper to find a iPhone 3/3GS than a 4 than a 4S than a 5. Please assume that I know and am aware of all the other benefits of newer hardware like cameras, running iOS 6 (in the case of the iPhone 3), more RAM/faster CPU so that cheaper hardware will likely be both older and slower. However, functionally with the network connectivity, is there a difference?
But for someone that will only call, text, use maps and very lightly use Safari, my thinking is that I shouldn't spend any extra money and get the oldest phone for a friend that is constrained to T-Mobile.
Does the T-Mobile network / infrastructure only work with 3G or am I incorrect in thinking that newer phones don't work any better with T-Mobile's 2012/2013 network frequencies?