The option to delete the whole call history or all SMS messages is very powerful, so it is disabled in BIG Launcher by default.
Enable Delete all for call history
To enable the “Delete all” option for calls, go to the BIG Launcher home screen, tap the Apps button, and enter this Admin command into the Search box:
admin set phoneDeleteAllCallsButtonShow true okConfirm and test call history deletion
A confirmation dialog for the Admin command will appear. Tap “Yes”. Now return to the BIG Launcher home screen and tap the Phone button. At the beginning of the call history list, you will see a new item called “Delete all”. When you tap it, another confirmation dialog will ask whether you really want to delete the whole call log. If you confirm, the call log will be cleared.
Enable Delete all for SMS messages
To enable the “Delete all” option for SMS messages, return to the BIG Launcher home screen, tap the Apps button, and enter this Admin command into the Search box:
admin set messageDeleteAllMessagesButtonShow true okConfirm and test SMS deletion
Confirm the Admin command. Then go back to the BIG Launcher home screen and tap the SMS button. At the beginning of the message list, you will see a new “Delete all” item. When you tap it, a confirmation dialog will ask whether you really want to delete all SMS messages. If you confirm, all SMS messages will be deleted.