How can I change the design theme?

Threema is available in a light and a dark theme. You can switch between the two themes here:

Android

Settings > Appearance > Design theme

iOS

Settings > Chat Display > Dark Theme

Windows Phone

Threema respects Windows Phone’s system-wide color-scheme setting, which can be adjusted here:

Windows Phone > Settings > Start + Theme > Background

Colored chat bubbles can be toggled in Settings > Appearance > Colored Chat Bubbles.

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