Since you added PayPal, you might as well throw Braintree in there. It's pretty great. I've been happy using it for an app I'm working on. Oh, and Mailchimp's A

Since you added PayPal, you might as well throw Braintree in there. It's pretty great. I've been happy using it for an app I'm working on. Oh, and Mailchimp's API, too. I have a feeling that this list is going to go on and on. http://www.braintreepaymentsolutions.com/gateway/api http://www.braintreepaymentsolutions.com/gateway/api http://apidocs.mailchimp.com/ http://apidocs.mailchimp.com/