My co-founder and I just launched MatchMoji! It's an iOS game where users try to match emojis with their facial expressions.
All of the processing occurs on-device and we use Firebase as a model server. There's a mode to help us train by uploading images, and we've built a pipeline to continually train and deploy the best model.
Please check it out and let us know what you think!
App Store link: https://itunes.apple.com/us/app/matchmoji/id1360888175?ls=1&...