Replication can often be an answer if the applications do a lot of reading (of course, replication isn't an answer to a performance problem if the database isn't the bottleneck).

But if you do a lot of writes (which is what the OP is doing if I understand him correctly) using replication can be quite tricky, and even if you manage to set up your replication schemes correctly (replicating both ways is far from trivial), and have changed your application so it can deal with such a scheme, it may not give a significant speed up.

Note that the OP is talking about a desktop application. Performance problems for such applications are typically not solved with replication or clustering.

I think the OP should first do some performance analysis to determine where the bottleneck is.