Warning / Advertencia.
DOOGEE shall not take any responsibility for phones that are updated not through OTA as we can not control the installation process. If a user downloads any of these firmwares and updates a phone not through OTA, shall any problem occur, it is the user’s sole responsibility.

For updates and access to tools, follow the following link.
http://www.doogee.cc/servicexiazai_detail/newsId=184.html
Remember that this tools are for professionals, do not attempt to update your phone on your own if you do not have previous experience in doing so, as you may damage your phone.
Hitman DG850
Build number:DOOGEE-Hitman-DG850-Android4.4-V02-_2014_1230
Update Content:
Solve the problem that the device crashes when playing game, playing video, and selfing
Link