A while back, Google said a fond farewell to the blob emoji that had been a core part of communication on Android for years, but now they're back as animated stickers in Gboard and Android Messages. They're usable in Android Messages no matter what keyboard you're using, and will be sent over RCS as any other stickers would. If the person you're texting does not have RCS messaging capabilities, they'll receive the blobs as MMS messages. In Gboard, meanwhile, they're normal stickers and will work as such; a GIF file will be uploaded directly into the conversation, document or text entry field, and if that particular text receptacle is not compatible with GIFs or image uploading in general, then nothing will happen.
Blobs are available effective immediately in both apps, and won't need an update to enable them. You can find them in both apps exactly where you would expect to find any other stickers. No small number of fans have been clamoring for the blobs to be given a second chance as normal emoji, available to use anywhere, but Google does not appear to be relenting in that regard just yet. It's worth mentioning that the blob emoji have still been available this whole time in some third-party keyboards, but this solution is both unofficial and not exactly ideal; unlike the original blob emoji that were built into Google's Android framework, these could suffer from compatibility issues in sending and end up displayed as normal emoji on the recipient's end.
The return of the blob emoji is part of a celebration of World Emoji Day, but there's no indication that they'll be descending back into the shadows once the day is over. The blobs were widely lauded as being cute and expressive. They were meant to represent everybody and yet nobody at the same time, but rather represent base emotions or the essences of actions, making them rather unique among emoji. Even so, Google eventually made the decision to give them the boot due to inconsistency over time with art for newer and older blobs, and also because the company wanted to make emoji that would more specifically represent all racial and gender groups.
— Google (@Google) July 17, 2018