I use Pimlical Android to do this. You can color code categories and set reminders with or without an alarm. It is a very powerful organizer with a great deal of customization. But that means it is somewhat complex to configure, and is a little pricey. If you are not afraid of the large amount of customization, and want a great organizer, I would highly recommend Pimlical Android. Also available is a Windows app that syncs directly by cable, or through the cloud. I've been using it for years and have not found a better organizer.