Redmi note 4 is a advanced version of Redmi note 3 and redmi 3s.Internal Rom of Redmi note 4 phone is more than Redmi note 3 and Redmi 3s.Redmi note 4 has advanced processor than note 3 and 3s. Redmi note 4 have 2gh Octacore processor while note 3 have 1.4gh hexacore processor so speed of a Redmi note 4 is better than note 3 and 3s.It available in 3 Ram versions 2gb , 3gb and 4gb.Camera of a redmi note 3 is 16 mp and Redmi note 4 is 13 mp but while you comparing both phone camera The camera quality both phones have almost same.Buy Redmi note 4 best budget phone.Go for it