Complex sentence: It received multiple large updates, the last being Windows Phone 7.8, which was released in January 2013 and added a few features backported from Windows Phone 8, such as a more customizable start screen.
Split into simpler sentences: It received multiple large updates, the last being Windows Phone 7.8, which was released in January 2013. It added a few features backported from Windows Phone 8, such as a more customizable start screen.