https://www.bleepingcomputer.com/news/microsoft/microsoft-to-do-beta-for-android-gets-dark-theme-in-the-latest-update/

Microsoft To-Do is a feature-rich task manager for Windows 10, Android, iOS and web. These features include the smart suggestion that lets you complete the most important tasks, jobs or housework and it also syncs the items between your devices.

After it was released for Windows 10 last month, the new dark theme option for Microsoft To Do is now rolling out to Android devices. The latest update for Microsoft To-Do (beta) on Android bumps it to version 1.37.7599 and you can download it from the Google Play Store.