This repository provides Swift Core ML implementations of popular transformer models including GPT-2, DistilGPT-2, BERT, and DistilBERT. It includes conversion scripts to export PyTorch models to Core ML format, custom Swift tokenizers (BERT tokenizer, GPT-2 BPE encoder), decoding strategies for text generation, and demo apps showcasing on-device inference. The models run entirely on Apple devices without server communication.