One would not have to create an app for a cell phone, merely create screens that could easily be viewed and manipulated on a cell phone.
JKB:
I respectfully disagree, however, the only example i can point to that most everyone uses is the google docs example, which i have already ceded is very spotty. An ap is usually the a+, #1 way to make everything as user-friendly as possible, even the best mobile-adapted site can't resolve to every type of phone, number of touchpoints etc. But, I digress.
Anywho, best of luck, DataBass. Let us know how it continues to turn out, and let me know if i can help with anything, i'd be happy to.