Payments

Ways to charge money. The split that matters for a small app is whether you are the merchant, or a provider sells on your behalf and handles sales tax.

3 tools

Paddle
Payments
Merchant of record for software and digital products. Paddle handles payments, sales tax, and compliance across markets.
Pricing as seen: See site. Paddle publishes all-inclusive or custom pricing rather than a simple per-card rate.
Polar
Payments
Merchant of record and usage billing for software, with subscriptions, credits, and metered events.
Pricing as seen: Free plan listed at 5% + 50¢ per transaction. Paid plans listed at $20, $100, and $400 per month with lower transaction fees (3.80% + 40¢ down to 3.40% + 30¢). A startup program was also listed.
Stripe
Payments
Payments and billing infrastructure for cards, checkout, and subscriptions. You are typically the merchant.
Pricing as seen: See site. Card fees vary by country and product, so this entry does not quote a rate.