It is equipped with high performance CPU chips which are relatively more energy consuming. Prolonged period of processor demanding tasks such as gaming and video streaming tend to cause the phones to warm up. Both cameras are so horrible! it is impossible for you to take good pictures unless supported by perfect light conditions. RAM management is poor, 3 GB RAM after installed 20 apps, there is only 700 - 800 MB free RAM available. Some kinds of vibration when phone is on charging mode and in hand, it is due to metal body, not suitable for usage while charging.