Unicode characters, like ♥ and ♡, cannot be used. Emojis are all in!
However, we do have to use our own emoji library, because the one on your device is copyrighted and we don't want to get into trouble! Some languages are not supported at the moment, like Hangul, Han, Cyrillic, etc. but, we are working hard to implement these in the future.
If you have any issue or the result is not what you expected, do not hesitate to contact us!