The market for online note app is almost saturated in China. As you know, people are used to OneNote, Evernote, Notion, etc. They are famous in China as well as out of the country. Hence, it's really hard to popularize a new note app in this kind of market.
Several suggests: 1. Discount is always welcome to everyone. 2. Ads for the people who really need the note app is helpful, like engineers.