If you've got the need for speed, the Samsung Galaxy S4 with LTE Advanced may be worth waiting for. This permutation of the Galaxy S4, which doesn't yet have an official name, is expected to offer downloads speeds twice as fast as those from the standard Galaxy S4. With that kind of bandwidth, Samsung claims users will be able to download a video that usually takes 3 minutes in a little more than a minute.
Of course, you won't be able to take advantage of those speeds until carriers roll out their own LTE Advanced networks. AT&T says it will begin offering LTE Advanced in the second half of 2013. Verizon has yet to announce a timetable for LTE Advanced, and while Sprint and T-Mobile say they have the equipment in place for such networks, neither has said when they will turn them on.