The profit is threefold:

• Not having to write a significant part of your app at all if you’re sharing from an existing iOS app.
• Improved performance for realtime applications like on-the-fly graphics and audio processing (for us this difference was significant – less than 25fps to flatlining 60+ fps)
• Not having to maintain multiple codebases in different languages.

All of those sound pretty appealing, but there’s nothing unique there compared to what is offered by just using the NDK with C(++), so a final one:

• Use a simple, modern and powerful language that – if you develop for Mac or iOS – already know and continue to improve your skills with.