From www.bleepingcomputer.com: Google NotebookLM has upgraded to Gemini 2.5 Flash, enhancing its research tool’s ability to generate more comprehensive responses, especially for complex multi-step reasoning questions.

The upgrade improves the tool’s reasoning capabilities while maintaining the existing Audio Overviews feature, which will not receive significant changes in this update.

Google is working on a new NotebookLM app for Android and iOS, set to launch on May 21.