I am using PayPal MPL in iOS because I need chained and parallel payments (split the fee between the seller and me). It seems that I can't find where the PayPal AppID's are located to complete this in the app delegate:
[PayPal initializeWithAppID:@"APP-80W284485P519543T" forEnvironment:ENV_SANDBOX];
//[PayPal initializeWithAppID:@"your live app id" forEnvironment:ENV_LIVE];
//[PayPal initializeWithAppID:@"anything" forEnvironment:ENV_NONE];
I registered my App on the PayPal developer website and I am given for sandbox a ClientID and a Secret, which are two separate numbers and cannot replace APP-8... I suppose that these are for the iOS SDK, however the SDK currently does not support parallel and chained payments, so the only alternative I would have would be to use HTTP requests. Furthermore when I open up the PayPal dialogue in iOS in Sandbox mode and enter my email and password it says that they are not valid.