I'm in the process of spec-ing out a rich application for personal finance management - a cross between tools like Quicken and Mint.com and a set of spreadsheet macros I created for personal use. It would be a simple matter to build it either online or offline (preferably both), but we all need to start somewhere.
So what's the best way you choose deployment focus with your projects? Do you deploy a desktop app for testing first and evolve to a rich, online application later? Or do you build a web-based system first and package it for desktop deployment later? Both are valid approaches, but I want to know which has proven the more efficient in the past.
In either case, the application will still be built somewhat the same - a separate database layer, business logic layer, and presentation layer. The question is more about the location of each (local or remote) and the problems that might arise by choosing one approach over the other.