Design of javascript desktop app for future conversion to mobile device

[gcassar]

I am about to write a Jasvascript desktop application. (It’s a mapping application using ESRI Javascript API) I plan to convert this application to run on Mobile devices down the track using Sencha Touch.
I don’t really have time to sift through all the documentation yet but wondered if there are some design considerations I need to take on board now within my javascript desktop web page.
Eg.
HTML elements / Styles / Page layout to use or avoid. That sort of thing.
Does anyone have a few tips or reference to the documentation I need ?

[mitchellsimoens]

It all depends on your UI but moving to mobile from desktop usually will require a different UI

[gcassar]

It all depends on your UI but moving to mobile from desktop usually will require a different UI

Thanks Mitchell and apologies for being vague. I am aware that I will need to break the UI up into components to make it workable on a mobile. Example: putting the query menu and results sections on separate screens or tabs. (And probably tweaking the CSS.)
When I do this, is it just a matter of creating the new mobile UI stucture with Sencha Touch and essentially calling the same javascript functions where appropriate that I have already written ?
If so, then I'd like to know whether there are types of document elements or styles that simply don't work well in the Sencha Touch application. Also do Dojo.connect events work the same ? I hope that makes it clearer.