Outlook
I will start this by simply saying that for many years I used Microsoft's Entourage software on the Mac as my primary email, calendar and contact application. While it didn't have all the features of Outlook, I also wasn't completely aware of what I was missing since I'd not really used Outlook by that point in my life. Entourage was discontinued after the Office for Mac 2008 release. It was replaced with Outlook for Mac. It was around that time that I switched from Entourage to the Apple Mail, Calendar and Contacts system that came baked into the OS. I never really liked it as much as I liked using Entourage since everything was kept in separate containers. Sure, the various applications could talk to each other, but if I wanted to go through my contact list in any meaningful way I had to open my Contacts application instead of just checking out contacts within the software. It was also around this time that I began using Outlook quite heavily in my professional li...