The cheapest option is almost always a compromise, and the newest phone from UK network EE -- called the Rook -- is no exception. It's being promoted as the cheapest 4G LTE smartphone on sale in the country, and at just 40 on Pay As You Go, it's going to be pretty hard to beat in terms of value for the data speed it provides.

However, the EE Rook is cheap for a reason. The specs aren't what you'd call high-end, but they aren't an absolute disaster either. We'll start with the aspect that's going to see the Rook struggle to win fans: Its screen size. The display is 4-inches, which was great when the iPhone first came out, but looks and feels pretty small by today's standards. The resolution isn't high at 480 x 800 pixels either.

The best news is Android 5.0 is installed, bringing the Rook right up to date, and from the screen shots it appears the level of customisation is kept to a minimum. A quad-core MediaTek processor with 1GB of RAM provides the power, and there's 8GB of internal storage space, plus the option to increase this using a MicroSD card.

A 5-megapixel camera is on the rear panel, but there's no flash, and a VGA front camera is provided for very low quality selfies. Finally, there's a 1500mAh battery inside. None of these are reasons to buy the Rook. That comes with the 4G LTE connectivity and the 40/$62 price tag for existing EE subscribers. Newcomers to the network need to pay 50/$77 for the phone.

EE is under new ownership, following an acquisition by British Telecom at the beginning of the year, and has been releasing a variety of well-priced, moderately specced mobile devices under its name ever since. The Rook joins the Harrier range, which consists of three devices, including a tablet, and was announced several months ago.