No, we didn't build an LLM from scratch but built on top of the open-source Llama 3.2. Most AI therapy apps I've tried seem to be just wrappers around the OpenAI API with a system prompt, but that gives very different results. We don't store exact chat histories, which are only locally on your device, but rather summaries and profile building. We have many security measures in place, and since we use our own hosted model, chats will never be sent to a third party like OpenAI.