TVCatchup has been a growing favourite in the UK in the past few years. Initially made popular by offering a web app for the iPhone, natural progression would dictate that the service would also be made compatible with Android devices. The problem -- the web app doesn't always work that well. And, native apps are always better to have. Now, that's what we've got, albeit currently in beta form.
It's a very simple app, but it doesn't need to be complicated. After all, it's for watching TV. All the channels available on the web are present, and as I write this, I'm watching some of The Big Bang Theory using it. The verdict, it's good. The stream quality is excellent, and it's so easy to use it's unreal.
The downside for anyone outside of the UK is that it's not available for you guys. When you open up the app, it checks your service provider and verifies whether or not you're able to make use of it. (Of course, you'll also need a TV License and all that to watch stuff as it's broadcast.)
But, fellow Brits, you can download it here and try it out for yourselves.