One of the most anticipated features for me coming in the Windows 10 April 2019 Update is Dark Mode. Although the October 2018 Update has the ability to display Dark Mode it is very limited and buggy. So here is a few Official Windows 10 Applications that have the option of Dark/Light Mode that are coming soon.

Mail App
Calendar App
Maps App
Edge Browser
To-Do App
Tips App
Weather App
Remote Desktop App
Skype
Sticky Notes