Ask HN: Best payment gateway for small transactions?

I have a web app that offers a simple service for a one time fee of $0.99. Payment fees are killing me right now as almost 50% of the revenue is going to fees.

I pay $100/month + 3%/transaction + $0.3/transaction.

All the gateways I looked at seem to have a relatively similar fee structure. Because of the low price of the service the $0.3 fee is really huge.

I don't need a store or subscription billing or anything fancy, I just want the customer to pay and I get a ping on an webhook. I really can't increase the product price either. It's a small impulse purchase, making it more expensive would completely remove any appeal.

I looked at:

- Stripe

- Podia

- Gumroad

- Mollie

Any other suggestions? Thank you very much.