The locking process for Kaptur is purely there to disable all editing functions in the Kaptur edit suite so the data (which is now in two places) cannot be changed by another person whilst you are working on the job in Kaptur. To ensure this safety function is implemented if you don't lock your job by tapping on the padlock icon in Kaptur you will not be able to edit your job in the tablet as all edit rights will be disable if not locked and any changes will not be saved.