# Device compatibility
Caffeine has done some pre-configured settings for some systems as a way to make sure it works correctly on your device.
# Device (ROM)
# Xiaomi (MIUI)
- Force "Compatibility mode" to be enabled
- Need to configure "Ignore battery optimization"
- Remove the restriction of the "Hide icon" feature to Android versions
# Samsung (One UI)
# Android 12+
- Force "Compatibility mode" to be enabled
- Need to configure "Ignore battery optimization"
# OPPO / OnePlus (Android 12+ only) / realme (OPPO ROM)
# Newer ROMs
Higher versions of OPPO ROM can cause Caffeine to not work due to strict background restrictions.
Community fix by Rory Church
- Set timeout to infinite
- Disable "Allow dimming" and "Compatibility mode"
- Need to configure "Ignore battery optimization"
# Older ROMs
For older versions of OPPO ROM, Caffeine can only keep the screen waking up at a dimmer brightness.
- Force "Allow dimming" to be enabled
- Force "Compatibility mode" to be disabled
# Expert mode
If you don't want to use pre-configured settings, you can config Caffeine manually by using "Expert mode".
To enable it, simply click "Version" 7 times and then click "Expert mode".