Moderator: Moved to vSphere Replication
vSphere Replication doesn't currently support multi-VM consistency groups. You could use array-based replication to accomplish this.
Often, in a tiered application stack, the changes only occur on the DB so the APP server doesn't need to be replicated at the exact same time. It might be worth testing and seeing what your application requires or how it functions if you aren't replicating them both at the same time.