In the processing options box, you will see the name of the current module and its parents. If a parent is selected, the updated/new record will only be passed to users that have that parent.
For example,there is an "Appointment" module and in the Data Source and an appointment was created for a customer called "ABC Components".
You may decide that this appointment should only be sent to users that have this account on their device rather than sending the appointment to all users. Selecting "Account" in the processing options box would ensure that it is only sent to users who have the parent account "ABC Components" on their device. If a module is related to more than one parent, for example an appointment could be related to an Account or a Contact, both parents can be selected by holding down CTRL and highlighting both. This would ensure that the new Appointment was passed to any user who already had either the Account or Contact on their device.
When a parent is selected, Swift MEAP™ will check to see if the parent record has any other children, if it does, it will download all children associated to that parent also.