Jeremy Burge, Emojipedia:

WhatsApp used Apple emojis on Android for years, and only recently created its own emoji set for use on Android and the web. Slack, too, offered Apple emojis on all platforms until today.

Whether these changes were due to pressure from Apple, or a growing realisation that this might not be the right way to go about cross-platform use, we don’t know for sure.

Other apps such as Signal and Telegram continue to use Apple emojis on Android.

That’s Android. How about using Apple emoji in your iOS app?

Last week app developer Sam Eckert reported that an update to his iOS app BitTracker was rejected by Apple due to lack of compliance with its guidelines for trademarks and copyrights.

Specifically, emoji use in BitTracker was called out as being problematic in both the iPhone app, and a small ? Chart Decreasing emoji used in the watchOS app was also an issue.

Jeremy goes on to show more examples of app rejection, and Apple’s inconsistency in using emoji in their own teaching materials.

At the very least, Apple is sending mixed signals. It’d be good to have a clear sense of what will fly and what won’t in terms of using Apple emoji in your own app.