The Asus Zenfone 2 ZE551ML was announced in 2015, January. Released 2015, March With 5.5 inches, 83.4 cm2 (~70.8% screen-to-body ratio) IPS LCD, Powered by Intel Atom Z3580 (4 GB RAM model)Intel Atom Z3560 (2 GB RAM model) and running Android 5.0 (Lollipop), upgradable to 6.0 (Marshmallow), the device delivered smooth performance and multitasking capabilities. Its 13 MP, f/2.0, AF rear camera captured crisp photos and 1080p@30fps video, while the Li-Po 3000 mAh, non-removable ensured long-lasting usage.