One of most useful tools for a busy day (and life) is a to-do list. And, arguably, the to-do list is one of the ubiquitous apps for PDAs and now smart phones. While I never much used my old Palm Centro’s Tasks app, I’ve used to-do lists almost daily at work. There’s something very satisfying about ending the day and seeing that list (long or short) with everything crossed off! Of course, if nothing or very little is finished, well, that can be a bit disheartening, but alas, not every day ends well. One of the first apps I got for my WP7 phone was a to-do list, in this case Compiled Experience’s To Do Today , and I’ve used the paid version for about a week now. How’s it working out? Pretty well, actually.