TheKeptPromise has released Subtitle Studio 1.0 (http://tinyurl.com/q5jrxlw), a subtitle adding app for Mac OS X. It costs US$9.99.
To use you drop your movie onto Subtitle Studio. The app will auto-search for missing subtitles. You can sync subtitle with a single button, hit save, and you’re done.
Subtitle Studio supports M4V, MOV, AVI, MKV and other files. You can embed your subtitles into a M4V file for the Apple TV, iPhone, iPad and other devices.