Pulsating heart emoji. "I can hear your heart beat." If that isn't the definition of love then I don't know what is. What is love! This emoji icon was the replacement for "Sparkling Heart" in iOS 5 but is still available and accessible like many others!
Emoji History The emoji code/ image log of changes.
This emoji was part of the proprietary / non-standardized emoji set first introduced by Japanese carriers like Softbank. These emojis became part of the Apple iPhone starting in iOS 2.2 as an unlockable feature on handsets sold in English speaking countries.
In iOS 5 / OSX 10.7, the underlying code that the Apple OS generates for this emoji was changed.