Implementing a Natural Language Classifier in iOS with Keras Core ML

IBM Watson NLC and Conversation services (as well as many other NLU cloud platforms) provide a Swift SDK to use in custom apps to implement intent understanding from natural language utterances. These SDKs and the corresponding NLU platforms are super powerful. They provide much more than simply intent understanding capability -- they also detect entities/slots and provide tools to manage complex, long running conversation dialogs. However, even for the most basic NLC inference, these SDKs depend on network connectivity, as the NLC model is run in the Cloud. By using Core ML models to run NLC and NLU algorithms on the device, we can provide similar functionality without relying on cloud inference.