I remember using a day planner and how thick it was with all of my calendars and my address book and my note pad and notes from different projects. Whew glad all of those things are now wrapped up in my mobile device.
I manage my appointments and grocery lists in my phone. There are a lot of apps on the market, but the best one is just the Reminders app on my iPhone. Also, the UFYH app is really good to help me keep my house clean. The cleaning mini challenges are great.