Handwriting memo "a Paper"

This app provides a sheet of paper to scribble your ideas boundlessly.
Boundless drawing area and natural writing feeling are the biggest features.
　
Features
- Boundless drawing area
- Natural writing feeling by a three types of pen
- Simple interface and intuitive use
- Quick startup and response
- Unlimited undo/redo
- Share as image
- Zoom view and linefeed
- Highlighter pen (Semitransparent pen) support
- Landscape view support
- Auto save by long-tapping Android back button
- Five ruled line types: None / Horizontal / Vertical / Cross / Music (staff notation)