Calvetica takes its name from the font Helvetica—a widely-used font known for its clean lines and aesthetic beauty. Like the font it's named for, Calvetica prizes its own great design. A calendar app that focuses on efficiency, beauty, and ease-of-use, Calvetica doesn't introduce a ton of advanced features; in fact, it offers little that the built-in Calendar app doesn't. However, as Calvetica's designers will stress, it's all about the implementation.
Calvetica uses (you guessed it!) the font Helvetica heavily in its design, with a bold display that just looks cooler than the default Calendar app. By default, data is imported from your Calendar app, including any outside calendars you have synced with your iPhone/iPod—Google Calendar, for example. From the month view, events are denoted with stylish, color-coded dots; a more precise view lets you see the events for a particular day.
It's when you add events to Calvetica, though, that the app really shines. Gone is the annoying scroll-wheel of times; instead, you tap on the time where you'd like to add an event, and then you just edit the description. If you'd like to set a precise time (rather than a plan 'o clock) the app makes it easy to do that, too. It takes two taps to add an event—two!—at least if you don't count the keystrokes required to title an event.
Other than its speed (it is fast) and its ease-of-use, there's not much else to Calvetica. It looks cool, and it supports no-brainer features like outside calendar sync, all-day events, and notifications. You don't need this app. But it does look very stylish, and it's hard to beat Calvetica in terms of sheer speed. If you want to add events more quickly, this is the app to get.