AllaboutWindowsPhone have posted the above chart from a series of battery drain tests they performed on the Nokia Lumia 1020 with each version of the operating system available to it.
What the test clearly shows is that Developer Previews are not optimized for battery life, and that users on these bleeding edge releases should set their expectations accordingly.
It does however also show that WP8.1 with Lumia Cyan is a significantly improvement over Windows Phone 8 on the same device, and AAWP notes it is now in line with other mobile operating systems.
The numbers above shows the latest version of Windows Phone, which drains less than 25% battery life at the 13 hour mark, is now better than the Galaxy Note II, though still somewhat off the pace of the iPhone 5.
Most of our readers felt the latest DP release of WP8.1 Update 1 has either maintained or improved their battery life. Does these WP8.1 Lumia Cyan numbers match the experience of our readers? Let us know below.
Read more detail at AAWP here.