The Microsoft To-Do app has a new update rolling out that brings support for hashtags and improved readability of reminders in tasks. The update is version 1.26.58 for those keeping score at home and has rolled out to the Play Store. If you have it installed, you should get the OTA update over the course of the next few days.
The big new feature is hashtag support. Now you can use them in your notes for tasks and can search for those hashtags later. Think of it as tagging of notes, something that other apps have done for a while now.