We're looking to hook up a credit card processing to our app. As cheaply and secure as possible :) We're running a subscription-based service therefore a solid recurring billing is a must-have.
Suggestions? Feedback on whoever you're using? Thanks!
I have used them very successfully in the past. They have an API in various languages that is really easy to implement. For recurring billing, store the card encrypted and bill whenever.
The big gotcha for us is that the reporting API (to get data on existing subscriptions/transactions) leaves a lot to be desired.
I always figured that you want to maintain your own transaction records anyway for internal accounting and metrics. If you do that then you really have 90% of the work already done for a basic recurring billing system.