Emoji icons can be activated for use on iPhones outside of Japan. To make it possible to type emoji icons using your iPhone keyboard follow these instructions:
1. Download Emoji Free! from the App Store on iTunes.
2. Run the app
3. Touch the Awesome, lets do it! button
4. Press the home button to quit Emoji Free
5. Navigate to Settings -> General -> Keyboards -> International Keyboards -> Japanese
6. Turn Emoji ON