Starting today, Sprint Galaxy Note 4 users can update with the Android 5.11 from Android 5.0, with build N910PVPU4COG5. The new version of the OS not only improves the performance of the handset but also fixes the critical vulnerability in Android OS, popularly known as the Stagefright.

The bug allowed hackers to hack into the smartphone by sending malicious codes through text message. These messages generally contain a link to a video file or an audio that causes the damage. Until now, the best way to deal with the vulnerability was to disable MMS messaging on the smartphone.

There's good news for owners of Samsung Galaxy Note 4 on Sprint's network who've been missing the MMS feature. With the recent Android 5.1.1 update, the bug has been fixed and people can now turn on the facility to share videos and audios with others using carrier's network.

Other notable improvements in the Android 5.1.1 update include device stability improvement, new and/or enhanced features and performance boost.

To update the Sprint Galaxy Note 4 with Android 5.1.1, owners should go to Settings > Software Update and hit the "Update Now" option. If the 5.1 OTA is not available, there's no need to worry. The rollout has just begun and will be available gradually to all owners. 

Important tip: Be sure to stall the stock recovery back on your device if you have custom recovery like TWRP installed on your phone. The stock recovery is a must-have for the latest Android 5.1.1 update.

It's worth noting that the Android 5.1.1 update is only available for the Sprint Galaxy Note 4 smartphone and is yet to be made available for Samsung's flagships on other national carriers in the US such as T-Mobile, Verizon, AT&T and US Cellular, among others.