Currently the only way to get feature changes that occur in the source GDB down to a mobile cache is to set the refreshData parameter to true when synchronizing data, in which case all of the data in the layer is replaced (Note: I have received very inconsistent information about this from ESRI in the past - many people seem to be under the impression that only the changes are brought down the client during synchronization, but based on my -- very extensive -- testing and work with Mobile, this is definintely not the case currently). Attempting to synchronize server-side changes to a large complex base layer such as parcels down to a mobile client is essentially impossible over a low-bandwidth connection (i.e., wireless aircard), which is a very typical scenario for a mobile deployment.
It seems that Mobile synchronization was designed entirely around the use case of sychronizing data edits done in the field up to the server. The use case of wanting to update base data in the field, with edits/updates happening on ther server, seems to have been completely overlooked. And based on my experience with end users and clients, this is a very common use case (more common in fact, than the field edit scenario). There are numerous posting on the Forums over time, on this same topic - I am clearly not alone in wanting better server-to-client synchronization support in ArcGIS Mobile.
ArcGIS Mobile should support efficient and fast data synchronization (of "deltas" or changes only) in both directions (i.e., to and from the server).
