On May 29th, 2013 Google rolled out an update to their popular app Google Calendar. The Google Calendar app (official) has always provided a clean user experience for users and is preferred to the default stock calendar for most users.
This new update added the ability to customize event and calendar colors directly from your device. I'm not quite that crazy myself but I understand that there are some people that color code different meetings and events to help them organize their day. This is now easier than before.
I'm more excited about the new Date and Time pickers. The redesign makes it a lot easier to quickly select a time of day on a dial like turn. Also, for those who do a decent amount of traveling the redesigned timezone picker makes it easier to find the city or time zone you are looking for.
As a last note, check out the repeat events menu to see the new clean day selector and other interface upgrades. Generally I'm also on the lookout for new features but a cleaner design does increase productivity and limits errors and mistakes when inputting meetings or events. Thanks Google!