Web Runtime Widget is a relatively new technology on Symbian phones. Basically it is an application written in html + javascript + css + ajax. Nothing but a complex web page. Nokia's attempt to catch Web 2.0 on their mobiles before it becomes obsolete. Unfortunately, it is available in new phones only. Like it supports some s60 3rd Ed FP1 with software updates, but not E51. I checked Nokia forums but there was no confirmed report that E51 will support WRT, even after a software upgrade.I was upgrading the software of my E51 anyway, so I decided to try a WRT post upgrade.
The easiest (and probably useful) candidate was Accuweather Widget, which shows (pretty good) weather information about a city. The whole package comes as .wgz file, and at least post software upgrade the file manager found an association with the extension and allowed me to explode the tarball as an application. So far so good. Now the application launches, but keeps showing me the weather of Paris. Not too useful for me, and I wanted to change the city to Bangalore.
And this is where unsupported platform hurts. I can't edit a text box in the widget. It'll just take the first keypress and hang. No further input is possible in a textarea. Damn, now I can't change the city. I wished I lived in a city started with A, D, G, J ... (ok you get the pattern). Then a brainwave hit. It is all Javascript so maybe I can edit that file to change the default to Bangalore. And yes, accuweather.js says somewhere if (!zip) zip = "EUR|FR|FR012|PARIS". Now to find out the Bangalore code, I had to search Bangalore in accuweather mobile site and from the URL location found it to be ASI|IN|IN017|BANGALORE.
But I am sure other WRT widgets will be complex enough, and won't fall for so easy hacks.