Quick heads-up if you're a Gemini user: AI typically retains your conversations and uses them for training, plus humans can review them too. To get around that, always start a Temporary Conversation — those aren't shared. On the mobile app you'll find it as an option in the top right corner.
One more thing worth mentioning: there was a recent arrest that came out of an AI. A woman was using AI like a daily journal, got upset about something, and mentioned "shooting it up." Before she knew it, police showed up at her door. Whether that's good or bad is up for debate these days, but it's a reminder that what you tell AI doesn't necessarily stay with AI.