Accept Mobile Payments

I plan to build a Mobile Shopping Cart Application, whats the best way to accept credit card payments.

I am targetin开发者_如何学编程g iPhone, Android and Blacberry devices.

Please suggest?

Incase someone else is also looking for the same thing, I came across 2 options :

1. iPhone IAS :http://developer.apple.com/library/ios/#documentation/NetworkingInternet/Conceptual/StoreKitGuide/MakingaPurchase/MakingaPurchase.html#//apple_ref/doc/uid/TP40008267-CH3-SW1

2. Paypal https://cms.paypal.com/us/cgi-bin/?cmd=_render-content&content_ID=developer/e_howto_api_ECOnMobileDevices

Thanks

Ravi Mudaliar