Talking of Paytm, just enabled BuyNowPayLater in Paytm for monthly limit of 50k.
It saves the trouble of recharging the wallet often. Works like a credit card. Can be used at tolls and daily payments at groceries, etc..
No charges, no taxes if you settle the bill in 30 days.
For Paytm shareholders, you are not going to get a rupee in interest cost/charges from me