No Swift support
I just bought Codebox (April 2016) and regret not doing a little more homework. I wanted the app for Swift snippets and the app doesn’t have support for Swift. It doesn’t look like it’s been updated since 2012 and the last Twitter posts from the author are from 2013 making any future support a bit unlikely. I would recommend looking online at something like GistBox which, while doesn’t currently offer Swift support either, is as least being actively developed.
Another option is to simply use something like Evernote. With great search and tags, it seems to offer the same as CodeBox, especially for languages missing syntax highlighting.
Simdude about
CodeBox