The Sony Xperia U is an Android phone with a 3.5 inch screen. Originally shipped with Android 2.3, an upgrade to Android 4.0 Ice Cream sandwich has brought the phone bang up to date. It's got a 5 megapixel camera, 1Ghz processor and 8Gb internal memory (only 4Gb is user accessible though).
The cheapest contract that we could find for this phone was from e2save, on Carphone Warehouse's own TalkMobile network. For just £19.99 for the phone itself and £7.50 a month you get 250 minutes, 5000 texts and 500Mb of data a month. This is NOT a cashback offer though, all you pay is £7.50 a month.