The Facebook application for IOS has been under a lot of criticism mainly because of the battery drain issues. A lot of users reported battery drain issues were related to Facebook app for IOS. Users not only reported the battery drain issue but also reported the heat up issue because of too much battery consumption. However, Facebook has finally released a new update to fix this battery drain bug.
Interestingly Facebook has not mentioned anything about the battery drain fix in the changelog for the latest update. This is quite surprising since it was the major issues that was addressed by the company in the latest Facebook app update for IOS.
However, Facebook engineering manager Ari Grant pointed out two major issues behind the battery drain on IOS. In his Facebook post he said the first issue was in the network code that never let the CPU to sleep thus leading to battery drain. The other issue was that audio session kept running in the background even when user has closed the application after watching some video.
Anyways, if you have not updated the facebook application yet then you should do it now to get rid of battery drain issues on your IOS device.