After it was released for Windows Insiders last week, the new dark theme option for Microsoft To Do is now rolling out to all Windows 10 and Windows 10 Mobile users. You'll find the option after installing the version 1.34.11781.0 of the app, and the dark theme actually looks more like dark grey.
On Windows 10 Mobile, the implementation seems not completely polished as of today. Indeed, when you select "Add a to-do," the text goes from purple to an almost unreadable black color, as you can see below. We hope this will be fixed in an upcoming update:
Dark theme remains a very welcome addition and we hope to see it land on other platforms in the near future. If you haven't tried it yet, you can download Microsoft To-Do from the Microsoft Store via the link below.