To switch to eraser, long press the primary button on your S-Pen.
Samsung S-Pen Air Actions
- Open your device's Settings > Advance Features > S-Pen >Air actions.
- Tap your desired app under Air actions.
- Find and tap Notewise. Make sure it's turned on. You can also customise actions for different gestures in the popup.
To learn more, here's a video tutorial from Samsung on Air actions.
Xiaomi Pen is only supported on Notewise 2.1.0 and above.
- To switch to eraser, click the primary button on the pen.
- To switch to the previously selected tool, click the secondary button on the pen.