I am using Lenovo Zuk Z1 from June 2016.This is the best phone in Rs 15000 range.
Camera Quality, Storage and Battery back up is USP of Lenovo Zuk Z1.
Lenovo Zuk Z1 comes with 3 GB RAM with 64 GB Storage space.As I think 64 GB memory is enough.
Camera Quality is also very good.Lenovo Zuk Z1 comes with 8 mega pixel front camera and 13 mega pixel back camera.
Battery back of Lenovo Zuk Z1 is amazing.18 to 24 hour battery backup, if anyone using in a good way.
Fast charging in Lenovo Zuk Z1 is also a good feature.Screen size is also good.
If you are investing Rs 15000, Then you should only buy Lenovo Zuk Z1.