Since there will be a Zen UI layer on top, you might not be able to fully appreciate the new Material design and several other things, Google has been raving about, but you will benefit from new backend features like a stock battery saving mode, new keyboard, lock screen notifications, better App management and better security. Zenfone 4, Zenfone 4.5, Zenfone 5 and Zenfone 6 all are expected to be updated to Android 5.0 Lollipop in the first quarter next year. Zenfone 5 LTE, PadFoneS and PadFone Infinity are also in the list. Asus doesn’t have a reputation for speedy updates. In fact, the entire Zenfone range just got updated to Android 4.4 Kitkat this month itself. We would be happy it manages to pull it off till the expected time frame. All Motorola phones, Sony Xperia Z series, HTC One M7 and M8, LG G3, Samsung Galaxy S5 and a few others have been officially confirmed for Lollipop upgrade. Asus hasn’t officially confirmed anything yet, so it would be wise to balance your expectations Source
