Open Camera - Open Camera is an open-source camera app for Android phones and tablets.
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
Secure Camera - Modern camera app focused on privacy and security with QR & barcode scanning.
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.
PhotonCamera - Android Camera that uses enhanced image processing.
Braintree - An all-in-one solution to accept, process, and split payments in your mobile app or online - from small business to large enterprise.