For Android:
- Open the Settings app
- Tap “Display,” then toggle the “Dark theme” on
On Samsung:
- Open the Settings app
- Tap "Display" and then "Dark Mode Settings"
On OnePlus:
- Open the Settings app
- Tap "Customization" and then "Preset Theme"
Note: Because not all Android devices have the same settings, if you are not seeing any options similar to the instructions above, contact the manufacturer for assistance.
For iPhone:
- Launch the Settings app on your iPhone or iPad.
- Tap Display & Brightness.
- Under Appearance, tap Dark to switch to Dark Mode.
To turn Dark Mode on or off from Control Center, pull down from the top-right corner of your device, then touch and hold the brightness control. Then tap Dark Mode On or Dark Mode Off. You can also set Dark Mode to turn on automatically at sunset or at a specific time
Note: Not all apps offer an official dark mode; some just have night themes that only work under certain conditions. But if you've updated to iOS 13 or your phone has the Android 10 update, both mobile operating systems support system-wide dark modes. But it will only apply to supported apps such as YouMail.