Use "Select" button in the waypoints list screen to enable multiple waypoints selection:
Pick waypoints:
And use right bottom delete button to delete the selected points.
Same as above, use "Select" button in the waypoints list, select waypoints and use left bottom Action button to export the selected waypoints.
This is it for version 1.1, I'm back to adding new features for the next version! If you like the app and would not mind supporting it, please review or rate the app. As easy as tapping here and leaving me a few words! Yours, Stan, the dev.