"You're under no obligation to choose a license. It's your right not to include one with your code or project, but please be aware of the implications. Generally speaking, the absence of a license means that the default copyright laws apply. This means that you retain all rights to your source code and that nobody else may reproduce, distribute, or create derivative works from your work. This might not be what you intend.
Even if this is what you intend, if you publish your source code in a public repository on GitHub, you have accepted the Terms of Service which do allow other GitHub users some rights. Specifically, you allow others to view and fork your repository within the GitHub site.
If you want others to use, copy, modify, or contribute back to your project, we strongly encourage you to include an open source license."
Source: https://help.github.com/articles/open-source-licensing/
"How can I report an app that infringes my copyright, trademark, name rights, or likeness?
If you believe that an app which is currently available on the App Store infringes your rights, contact Apple's legal team for assistance and include specific information about the infringing app.
If the app or app content is unavailable on the App Store, contact AppStoreNotices@apple.com directly and include specific information about the infringing app or app content."
Source: https://itunesconnect.apple.com/WebObjects/iTunesConnect.woa/wo/9.0.0.13.7.2.7.9.3.1.2.3.3.1.1