After announcing in October, NotebookLM has fully rolled out chat history, while Google AI Ultra subscribers now have expanded usage limits.
Chat history lets you continue a conversation from the web on Android/iOS, or vice versa. NotebookLM timestamps each response with the day/date. Tap the three-dot overflow menu to find “Delete chat history” and start over. Your chat in a shared notebook is only available to you.
As of today, Google says this capability is “rolled out to 100% of users across mobile and web.”

Meanwhile, after teasing earlier this year, Google AI Ultra subscribers now have expanded NotebookLM access.
For the most part, AI Ultra’s usage limits represent a 10x increase over AI Pro. Subscribers paying $250 per month get 5,000 chats, 200 Audio Overviews, 200 Video Overviews, 1,000 Reports, 1,000 Flashcards, 1,000 Quizzes, and 200 Deep Research generations per day.
You can have 600 sources per notebook compared to 300 with AI Pro, while notebooks can have 1,000 users versus 500.
It’s the “Highest” (versus “Higher”) limits for Infographic and Slide generation, as well as Gemini models. Finally, AI Ultra users are the only ones who have Watermark Removal for Infographics and Slide Decks, like in other Google apps.
FTC: We use income earning auto affiliate links. More.
Comments