O2 UK is promoting Windows Smartphones. They are currently running a promotion on their front page and in-store where they are offering a £40 discount on the Nokia Lumia 930 and £39.99 on the Lumia 735.
This brings the Windows Phone flagship Nokia Lumia 930 down to £29.99 upfront and only £23.50 per month, and the Lumia 735 to £0 upfront and only £14.50 per month.
You can also get the Nokia Lumia 635 for £12.50 per month and £0 upfront cost.
Hurry up; the offer is valid till 27th May 2015.