XDA developers performed a miracle once again and OnePlus One has gained the early builds of Lollipop 5.1. The latest version of Android there is used by the owners of OnePlus One in the latest version of the ROM. At the moment, Android 5.1 is stated to be at work stage, that is why it is obvious that the work with this OS will have a lot of bugs and issues, as the development of it is still at early stages.
One of the advantages of the new version of Android OS is that developers for CyanogenMod work extremely quickly to debug the system and the users can even monitor this process on daily basis. In fact, the Android builds, that are now shared by developers are the CyanogenMod 12.1 for OnePlus One. At the moment there are no official builds that are revealed to the public.
One of bugs that are founded and waiting for repairing is the process of force closing of settings. Every time you are trying to select and order tiles for settings they will close, as well as Alarm that is always force closed. Any other information concerning Alarm is not available, so the Alarm may not even work at the moment. Build-in message app also closes every time when the device gets a message, however, any other messaging app works as it should. The last, but not the least, any process of installation will be marked by the package installer crash. However, the installation of the app will be completed successfully and the app will work in the ordinary mode.
In conclusion, it seems that the bugs of the early builds of Android Lollipop 5.1 are not that deadly for the system, so it is possible to try this version out. More than that, thanks to fast and operative work of developers that bugs will be corrected in no time.
At the moment, owners of OnePlus One are waiting for official Android 5.1 reveal so they will be able to implement enhanced native features like HD voice calling.