Say what you will about the official Twitter client, at least they're trying. The UI is still a little odd, but the beta is showing signs of improvement. For example, a recent update added support for immersive mode on KitKat devices.

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Immersive mode is different that the transparent system bar interface, so don't get too excited. Immersive mode hides both the navigation and status bar for a full screen experience. The current beta includes immersive mode when you open a picture from the stream.

The beta version is 5.2, and 5.1 didn't have this as far as we know. So it's a fairly recent change. If you want to get on the beta bandwagon, you'll have to be part of the beta program.