Sony Xperia XZ1 User Manual page 37

Using Group Calling
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During a call, Add call
Call History opens.
Enter phone number
Call is added.
・ Alternatively, Tap
for contact in Call History to add
call.
When the other party answers,
Group Calling starts.
Merge
Using Caller ID Notification
In Home Screen, (Apps)
Settings Calls
Call settings open.
Additional settings
Caller ID Hide number /
Caller ID is set.
35
(Phone)
Show number