TeuxDeux is a really simple cloud based to do app (for web and iPhone) that continually syncs as long as you are online. This is for individuals rather than a company or group of people.
There are lots of tools out there that cater for group working. I love a list and we find that keeping it simple like this is such a time saver. So basically you can add, cross off and shunt to a different day or list. You can also add live links so it’s easy to go straight to the relevant website. It is a paid app but very reasonable - $2 or $3 per month. Works in a browser for desktop and you can download from the app store for devices.
