[perfopt]

I have not seen a single eatery that does not accept cash.

Booking bus tickets - RedBus and other portals accept credit cards. To use cash one must book at the terminal.

[devoutsalsa]

I couldn't pay for lunch at my friend's office. They only accepted UPI as payment. It would have been nice to be able to pay for tuk-tuks and car taxis without using cash, too. If you only have "large" bills, the drivers never seem to have enough change.

[tamirzb]

RedBus and many other Indian apps & websites don't accept foreign credit cards. It can become a real headache when traveling in India as a foreigner.