MPen — 68WIN

Translucent color
You can use it like a highlighter with a translucent color compatible pen.

Undo/Redo
MPen keeps track of 8 undo levels. Usability like a desktop application.

Multi-language
UI supports English and Japanese.

For Windows 8.1/10 users:
There is a problem that you can not click on the touchpad while pressing the letter key. Improved by setting "touchpad sensitivity" of touchpad to "maximum sensitivity" in your Windows settings.