I have used this app when I was in school it helped me a lot to recharge my mobile, I have earned around 900 rupees from this app.
It even pays for per invites sometimes it gives 350 rupees per invite, there are many similar products in market but mCent is the only one which pays for each and every offer that it promises and comes with new offers this is the reason I use this product.
If you have not used mCent by now you must use it this is very good app to earn money by completing offers.