In 2016, SwiftKey released Swiftmoji, a new keyboard with predictive emoji, to make it faster to insert the colorful little characters into your messages and status updates. Swiftmoji worked essentially the same way SwiftKey's main keyboard did, with autocorrect and predictive typing, but with the distinction that it featured an additional bar at the top of the keyboard to display emoji suggestions based on context. Two years later, SwiftKey is finally shutting down Swiftmoji, as the app is now redundant and most of the functionality has already been rolled into the standard keyboard.
In honesty, not much has been lost now that Swiftmoji has been officially declared dead. The keyboard had not seen a single update since October of 2016, which included "support for the latest Android N emoji." The app also only had a total install base of between 500,000 and 1 million, which pales in comparison to Swiftkey's 100+ million installs.
The "when tears of joy become tears of sadness" emoji
Predictive emoji suggestion, Swiftmoji's crowning feature, is already present in the much more widely-used SwiftKey app, so there's really no reason to continue using Swiftmoji at this point. However, if for some reason you prefer Swiftmoji's layout or color scheme, the app will still be available for new and old users to download. The drawback is that it won't receive any future updates, but then again, that's already been the case since 2016.