There are some rumors about Xiaomi Mi4 phone, it will full metal frame design, smaller bezel, but the body will be longer than Mi3. There is no surprise on body thickness. From the leaked photo, the new Xiaomi Mi4 phone looks like OPPO Find 7 or Oneplus one.
The disposition aspect, Xiaomi Mi4
will use the super quad-core processor, which has not be released yet. [source]