App is http://www.expresii.com/ you can see its watermark briefly in the bottom right corner of the Kamvas screen.
I'm guessing this isn't strictly a feature of Expresii, but probably something native to the Kamvas 22 Plus.
The machine is out in China, Hong Kong and the Philippines, as mentioned here:
http://www.expresii.com/blog/lenovo-yoga-duet-7i-e-color-pen
Adobe has always been trying to address the 'fat pixel' problem. In a previous app 'Adobe Eazel' they tried to solve it by generating many vector shapes to mimick watercolor on the ipad, but seems they also think it's not a good idea afterall so that ditched the app. You can take a look at this technical review http://www.expresii.com/blog/innovations-in-digital-painting-tech and see if you another approach Expresii uses to tackle the problem.