Nokia Lumia 710 inc £10 Top Up & £20 voucher for apps, on Orange, T-mobile or Vodafone (Windows Phone) - £109.95

£20 more on O2 or £25 more on 3.

EDIT: Changed deal to CPW as they do it cheaper on their site now too and offer a £20 app voucher with it. "*This offer is available exclusively to Nokia Lumia 710 bought at Carphone Warehouse before 3rd July 2012. After having owned your phone for 14 days visit www.nokiafreeapps.com to claim your free £20 apps voucher. Claim by 31st July 2012."

You can of course still buy from mobiles.co.uk (all bundles are 5p cheaper), just without the voucher. http://www.mobiles.co.uk/orange-nokia-lumia-710-pay-as-you-go.html O2 and 3 bundles are actually £10 cheaper on there than CPW BUT once again, no app voucher.