是可以 共用data的，

Share Data Among
Apps

iOS provides powerful connectivity options for sharing information among the applications installed on a device. Using a URL-based syntax, you can access data from the Web, as well as pass information to other installed applications, such as Mail, iTunes, and YouTube. Your own application can declare a unique URL scheme, allowing any application to collaborate and share data with your app.

原文：http://www.cnblogs.com/guligei/p/3512621.html