As I continue to think about the design of CrowdNotes, I think back on a podcast I heard some time ago, wherein Jeffrey Zeldman described the (then) latest A Book Apart offering, Mobile First. The book, written by Luke Wroblewski, basically gives a super quick overview of why you would want to start planning your web experience by planning your mobile web experience first.
I'll be honest: I haven't read the book yet. It's on my list of things to do, honest! But just from the one podcast - of which less than 20 minutes were devoted to Mobile First - it really hit home for me. The reason you start with mobile first is because that's your constraint. You want the mobile user to have access to all the important stuff in your web app.
Think about it: let's say you're visiting the mobile version of an airline carrier's website. Since you're on your phone, chances are you don't really need to know what the top deals are for flying to Timbuktu, nor do you really need to know about the latest planes the airline just bought. No, when you're visiting an airline's mobile site, chances are you want to know if a flight is on time, check in, pull up your boarding pass, or maybe (maybe) book a flight.
Thus, if a person is visiting the main site via their laptop or desktop, don't you think that those same things should be front and center as well? Does it make sense for an airline to hide those really important actions (flight status, check in, boarding passes, book a flight) amongst all the news, deals, etc? No, it doesn't.
So basically, the point of all this is simple: by designing the mobile experience first, you'll be able to better design the full experience later. Yes, it may take more time; but in the end, you will have a much better sense of what your app is supposed to do and how people will endeavor to use it!