Recs.
Updated
Sunrise [free, no ads] is a calendar app for iPhone that emphasizes clean design and integration with Google calendar and Facebook.
SpecsUpdate
Pros
Pro Beautiful, detail-oriented and useful design
Sunrise isn't just pretty. It pays attention to detail by showing a small countdown until the next event, adds contextual icons to events that give a quick overview of all events at a glance, among many other nice touches.
The integrations and design make the app incredibly useful for managing the day. It packs a lot of functionality in a good looking, clean, and minimalistic UI.
Pro Pulls real-time event information from multiple services
Sunrise makes it easy to manage events set in Google Calendar, Facebook, Eventbrite as well as other services. In Sunrise, the information is seen as if each service has been visited individually. Additionally, the integrations provide functionality for interacting with these services such as being able to RSVP to an event from within Sunrise app.
Pro Extensive integration
Sunrise integrates with most major calendar services, such as iCloud, Google, and Exchange. Other services are supported as well, such as TripIt, Evernote, Asana, Github, Facebook, and LinkedIn. While most of these integrations are used for scheduling, other information is used as well; such as basic information about individuals who are attending mutual events.