2012

18 January 2011 PayPal Mobile Express Checkout Library Developer Guide and Reference
The sample application implements the payWithPayPal() callback method in the class that
gets the button, ReviewOrderViewController.
UIButton *button = [[PayPal getInstance] getPayButtonWithTarget:self
andAction:@selector(payWithPayPal) andButtonType:BUTTON_278x43];
The getPayButtonWithTarget method follows standard memory management conventions
and is autoreleased.
Redirecting Buyers to PayPal
Whether you place the PayPal button in your mobile application or on your mobile website, use
the same redirect to PayPal.
https://www.paypal.com/cgi-bin/webscr?cmd=_express-checkout-mobile
&drt=valueFromMobileExpressCheckoutLibrary&token=valueFromSetExpressChe
ckoutResponse
Completing the Payment
Whether you place the PayPal button in your mobile application or on your mobile website,
complete the payment by sending GetExpressCheckoutDetails and
DoExpressCheckoutPayment requests from your mobile website.
IMPORTANT: Never send Express Checkout requests from your mobile application directly to
PayPal. The requests require your PayPal API credentials. Placing your credentials on mobile
devices exposes you and PayPal to unacceptable security risks. Send Express Checkout requests
only from secure servers.
If you place the PayPal button in your mobile application, monitor the web view for the redirect
from PayPal to the returnURL or cancelURL. Set these URLs in your SetExpressCheckout
request. Complete the payment only if PayPal redirects the buyer to the returnURL.
For more information on the Express Checkout API, see:
 Express Checkout Integration Guide
 Name-Value Pair API Developer Guide and Reference
 SOAP API Reference