With months still to go before the official release of iOS 7, there's one built-in app replacement category that's found a sweet spot -- the calendar. If you're not a fan of Apple's default appointment management approach, you have a slew of alternatives to choose from.
Fantastical, Sunrise and Calendars+ all deliver UI enhancements and quick entry savvy; Cue, Tempo, Donna and the Google Now elements of the Google Search app focus more on delivering "smart assistant" functionality. These next-gen applications use a bit of anticipatory computing to suss out what you're likely to want to know next, much as Apple's upcoming iOS 7 "Today" feature is supposed to do. (Developers building tools that behave like a human assistant may need to be particularly careful about their "gendered" branding.)
The field may be crowded, but Cal, the latest entrant, has a leg up: millions of users are already happy with a sister application. Israeli entrepreneur Omer Perchik and his team at Any.DO started off with their eponymous app, a slick and sensible to-do manager for iOS, Android and Chrome. Any.DO has proven to be a hit, with its "have a great day" attitude, easy task entry and a solid synchronization story to the Chrome plugin; I particularly like the way the plugin puts a next-action field right into the context of a Gmail message, encouraging you to write down what you have to do.
Cal, which spent the spring in private beta, is the datebook pairing for Any.DO's task list. With lovely photo theming and easy Facebook or email sign-up, you can quickly show any of your iOS calendar items (synced natively with Google Calendar or Exchange) with lots of context: who are you meeting, where are you going and more. Each invited contact can be messaged, called or emailed with a single tap, or you can check the location map to know where you're headed. Right now you'll get birthday reminders if you link to Facebook, but some additional social integrations will be coming soon.
Aside from the ample visual glitz (and audible glitz; the app plays a brief music video in the background on first launch, which may take some users by surprise), there's an interface concept that delivers some different information than most other calendar apps. Cal includes your free time as "gaps" on your calendar, which are directly addressable for creating appointments. "We believe [the gaps] are key to help you have a good day," says Perchik. "Used intelligently, these 'gaps' are true opportunities to help you find the perfect balance between work and play."
If the Cal and Any.DO interfaces seem surprisingly iOS 7-ready, that's a happy alignment. Perchik told Mashable that he was "humbled" to note the similarities between his apps and the new direction for Apple's mobile OS when it was revealed at WWDC.
Cal is a free download in the App Store for iPhone or iPod touch. An Android version is planned soon (but apparently not soon enough for this cranky band of Facebook commenters).