Phone cheap and very powerful. Runs Android Kit-Kat and has an owner EMUI 2.3 interface. Normally a migration to 3.M0 Emotion is scheduled for December (according to sources) and finally the passing Lollipop next year. Interface a bit confusing at first use, but we made it very quickly. Some very interesting utilities to accurately manage several types of mode of use. An economy mode Type S4 / S5 allows to use the phone to its minimum and extend the life of the phone. Fluid fast for me to have the phone.