I think it would be fun to have Whatsapp integration, and I can easily send pictures, notes, voice notes etc to the journal. The other part could be to have a simple chat bot that provides prompts throughout the day, like "what are you doing right now?" or "take a selfie with whoever you're with."
Interesting. I've seen people using telegram to post messages to their Roam graph, it will require some significant work considering this is an offline-only app. But then again, if I do support all these log types, why not just go to the app directly? I do like your auto prompt feature and have thought about it as well (or even support different scripted prompts as plugins), some people do like the prompt and structure, maybe someday when there is enough user interests...