The iOS Calendar app is pretty basic, but for a lot of people, it gets the job done. If you're left wanting more, take a look at Horizon Calendar, which is US$1.99 in the App Store. We've taken a look at an earlier version of the app before, and this next generation, released today, adds more features and improves the GUI.
Horizon Calendar is part calendar, part weather app. It pulls your current calendar info from your iOS device and stays synced to the cloud. The app arranges your info into a very nice set of screens that is easy on the eyes and well-organized.
Weather is the other big feature of Horizon Calendar, so as you plan an event occurring within the next two weeks, you'll see a weather forecast. That's pretty handy, especially as better weather starts to roll in. If the event is in another location, you'll get the forecast for that area instead.
The app also features natural language event creation. If I say "Set up a 2PM meeting Friday in Chicago with James" the app adds the event details without my having to fill in fields. Even better, when I look at the event, I see a weather forecast for Chicago for this Friday. That goes a bit beyond what Siri can do when creating events.
Also new to this latest version is intelligent lookup. If I have a lunch meeting at the Olive Garden restaurant, for example, the app will assume that I mean the closest Olive Garden just as I start typing 'Oli..'. and fill in the location. It would be nice to use that info as a link to my favorite navigation program, although the app currently doesn't have that capability.