I would like to see a decent example of a mobile web app using the Sencha framework with a client side DB accessed with SQLite. I\'m currently digesting JqTouch and kinda ge
Sencha is client-side Javascript, so your application actually runs on top of Safari. That means you can forget about accessing (or installing) your own SQLite database from within the browser sandbox.
Having said that, you want to learn some new tricks, so why dont you read up on localStorage and DOM Storage. Basically the HTML5 specification allows for offline database storage based on SQLite (imagine relational database cookies). There is 1 per domain and they can be up to 5MB in size. I believe the iPhone supports this as well.

Here are some links: Introduction some API Information and a nice little blog entry by a chap called Ben Lister