Accessing speaker notes on a mobile device during a presentation can be done through PowerPoint's mobile app. When you open your presentation in the app, switch to the presentation mode, and you should see an option to view your notes while the slides are displayed. This feature allows you to scroll through your notes discreetly while presenting, but the exact steps might vary slightly depending on your device and app version, so it's advisable to familiarize yourself with the app beforehand.