It also will fix the battery life issues users have been having with the device since updating to Android 4.3. MK2 officially began rolling out on Nov. 30 and Sprint users should have already received a download notification for it. The last major software update for the Galaxy S4 was Android 4.3, JellyBean which brought several changes to the device including a Samsung Knox security update, enhanced multi-window mode, improved camera features, bug fixes and general performance enhancements. TRIM support will be added to improve performance along with Galaxy Gear support, Driving Mode, voice commands and Samsung KNOX compatibility. Despite other carriers having issues with the software's rollout, T-Mobile users seemed to experience no issues with it. The carrier reissued the update shortly after and seems to have corrected some of the issues, but this minor update should finish the job when it rolls out. Samsung Galaxy S4 User Guide {PDF}