I am currently owning two Micromax Unite A106 and they seemed to very good in this price range of under 5500 Rs. They major attracting feature in the phone is the multi language keyboard and inbuilt Kitkat OS. Though you can upgrade it to higher but I will not recommend due to lack of space.
In phone you get a quad-core processor and 1 GB RAM and there are two variants having the 4GB and 8 GB ROM.
I would recommend it around price 5K and around Rs 3500 if second hand purchase.