Android
Turn Contact Sharing via Bluetooth On or Off auf Android
When you pair an Android phone with another Bluetooth device, such as a car infotainment system or a headset, Android often shares your contacts and call history with it automatically. This happens through a permission tied to each individual paired connection, not through one global switch for all Bluetooth accessories.
That is why turning off sharing for your car does not affect a paired smartwatch or headset, and vice versa. Each device keeps its own setting, so you need to check the permission separately for every accessory you connect.
To change it, go to Settings ➔ Connected devices ➔ open the device settings for the paired accessory ➔ then enable or disable Contacts and call history sharing.
Turning this off stops the accessory from displaying caller names or contact photos, showing only numbers instead. If you rely on your car display or headset to announce who is calling, keep sharing enabled for that specific device.
If contacts are missing on a paired device even though sharing is on, the issue is usually a sync delay or the accessory's own contact storage limit rather than this Bluetooth setting.