I love this little app which manages my to-do list, reminding me what’s outstanding and allowing me to prioritise tasks. It synchronises my iPhone and iPad and there’s a web-based synchronisation tool as well (although I never use it). I no longer have scraps of paper and assorted, often-forgotten scribbles in my notebook – it’s all centrally managed and readily available.
Osmond Ergonomics 
Hi Guy
you should check as well Beesy an iPad To-Do and note taking app http://www.beesapps.com/beesy-ipad-to-do that integrated notes from meeting in a smart To-Do organizer. Really efficient for those of us of have lots of meeting.
they currently lack of iPhone sync at the moment but the devs at http://www.beesapps.com said they’re on it for a future release.
Beesy looks promising. I have bought the app and will report on it in due course.