How to get the original_application_version (the first purchased version number) out of iOS Receipt in iOS 11?

Question

I have a paid iOS App.

I need to get the original_application_version number (the first version purchased by the user) from the Apple AppStore Receipt.<

Answer 1

All receipt fields are in binary format within application receipt. You should use any kind of app receipt decoder in order to get original_application_version. It is always good thing to validate app receipt before using its contents. For example, you can use RMStore framework (RMStore). It contains receipt validator as well as decoder. Example Obj-C source:

RMAppReceipt *appReceipt = RMAppReceipt.bundleReceipt;

if (appReceipt != nil && 
    [appReceipt.originalAppVersion length] > 0 && 
    ![appReceipt.originalAppVersion isEqualToString:@"1.0"]) {
    //Process your original app version 
} else {
    //Probably it is sandbox mode or app install via Xcode
    //Or maybe you should force app receipt refresh
}