Freecharge is one of the best recharging app as it dont lag in bill payment to any operator rather it works instantly.
There costumer service is very good as I have experienced. One thing I dont like it only for one reason because it is associated with snapdeal and I dont like snapdeal.
It actually displays the accurate telecom operator plans which are currently running in the city. One benefit is if you withdraw all money to your account it will accept ti but other apps dont want your wallet account to be nill they also keep some percentage.