I want to integrate PayPal payment facility into my native iPhone application without using web interface so user does not have to leave from the current application. How can it be possible ? Should I use SOAP XML request/response mechanism? I come through following link http://www.slideshare.net/paypalx/learn-how-to-use-paypal-api-to-monetize-your-mobile-app. It contains In application Mobile Checkout via Mobile Web slide that represents the sample UI to access PayPal but how can I implement the same thing? Is it legal to use PayPal to deliver virtiual goods/Application Functionality or Apple can reject this ? Thanks.