The CFBundleShortVersionString
in your Info.plist identifies the version string for your app, such as 1.0 or 3.5.1. As your error implies, it is required in the Info.plist.
Simply open your project's Info.plist, choose Add Row, and enter CFBundleShortVersionString
, which may change to "Bundle versions string, short". Set the type to String and the value to a version identifier for your app; use 1.0 if it's the first version. Now re-archive.

You should also be able to change the version string by going to the General tab of your target in Xcode.
