The server-initiated and client-initiated Mobile Workflow models can coexist within one Mobile Workflow package.
A server-initiated Mobile Workflow is always initiated by a notification. Unwired Server receives notifications from a Notification Mailbox account and, in turn, delivers a notification message to an individual device based on configured distribution and matching rules. The matching rules are used to indicate whether a notification should be sent to a particular Mobile Workflow or not. Once a Mobile Workflow is sent to a user, the extraction rules are used to pull values out of the notification to be used as parameter values.
With the client, or device-initiated Mobile Workflow, the user can open the workflow form on his or her mobile device and create a mobile business object (MBO), which is then replayed against the linked server MBO package. You can also run object queries to retrieve existing MBOs, at which point you can then perform update and delete operations on those instances.