I needed a way to set & get a user's username and/or password to have it preset for the login screen. I guess with handheld devices it is a bigger inconvenience to not have that feature.

This workaround utilizes the HTML5 localStorage feature. I found a useful article here that helped me discover this.

in the onSuccess block of your login action add this little if statement
Code:
success: function(response){
                    if( ('localStorage' in window) && window['localStorage'] !== null ){
                        localStorage.setItem('user_name', loginForm.getValues().username);
                        localStorage.setItem('password', loginForm.getValues().password);
                    }
             ...
}

Then at the bottom of your login.js file (after the formPanel has been created) add this if statement.

Code:
        if( ('localStorage' in window) && window['localStorage'] !== null ){

            if( localStorage.getItem('username') !== null){
                loginForm.setValues({username: localStorage.getItem('username')});
            }

            if( localStorage.getItem('password') !== null){
                loginForm.setValues({password: localStorage.getItem('password')});
            }
        }
Now I am new to HTML5 and Sencha Touch, so I am not sure how much I trust leaving the password in local storage, but at least you can if you want now.

Any thoughts on this?