It's more about the cards you have than platform offers now. Tata Neu gives flat 5% with NeuCard Infinity, Google Pay also gives 5% using Axis Ace, Airtel app gives highest 25% on ADTV recharge with Airtel Axis Card. 2% on Amazon using Amazon Pay ICICI Card.
In general, if holding any Rupay Platinum Debit card then use it on Friday on Amazon to get 20% off up to 100 in a month.
Also, for regular amounts like 300-500 you can prefer Payzapp which gives 5% cb up to 21 in a month, applicable on UPI also, not restricted to specific card