Skyscanner - Skyscanner.com compares over 1000 airlines to find you the cheapest airfares, fast.
Stripe Billing - A set of tools for billing and subscriptions
KAYAK - KAYAK is a travel search engine that searches hundreds of other travel sites at once. Our helpful tools & features find you the information you need to make the right decisions on flights, hotels, rental cars and vacation packages.
PayHere - Run a services business or startup? Charge recurring and one-off payments with beautifully designed payment forms. Get up and running in less than 5 minutes!
Momondo - Find cheap flights with Momondo.
Square Installments - An easy way to offer monthly payment plans to your customers