Max isn't a fan of the Android Emoji's. He thinks they look hideous. How can he use the ones from the iPhone? Leo says that emoji's are very popular, and there actually is a standard based on unicode. Each OS draws that differently though.
Clinker has an app that has a keyboard with iOS emojis. But no one else will see them. Twitter has it's own version of emojis as well. Here's a thread on XDA Developers about this. The chatroom says SMS Messenger Pro is the answer. The challenging part, however, is that Max wants to keep using his Swiftkey keyboard.
Find a comparison of iOS and Android emojis at explodedsoda.com.