Piano - Piano lets you quickly learn the piano or other musical instruments using cell phones and tablets, and also contains magic tiles and different mini-games.
PayPal - PayPal is the faster, safer way to pay online without sharing financial details, send and receive money or accept credit and debit cards as a seller
Guitar - Git GUI Client. Open Source, Free Software (GPL v2). Run on Windows, macOS and Linux.
Stripe - Online payment processing for internet businesses. Stripe is a suite of payment APIs that powers commerce for online businesses of all sizes. Use Stripe’s payment platform to accept and process payments online for easy-to-use commerce solutions.
Braintree - An all-in-one solution to accept, process, and split payments in your mobile app or online - from small business to large enterprise.
Chargebee - Chargebee lets you manage subscriptions and payments at scale, handle custom recurring billing scenarios, reduce subscription churn and simplify accounting.