The Tempo calendar app attempts to improve on the default calendar program for the iPhone — and largely succeeds — by pulling information from multiple accounts, adding relevant information such as meeting locations from e-mail accounts and letting users text or call contacts from within the app. Having all of that information centralized in one location is incredibly useful, and the app is designed to pull in e-mail attachments from your accounts to make items like meeting agendas or presentation materials easy to reach from your calendar.
It remains, however, a work in progress. Users can’t, for example, add the names of attendees to events — one of many features developers promise are coming soon. Also, sometimes the app does things like pull the wrong similarly named contact from your phone book into your calendar. Still, the app gets better the more you use it and is an elegant alternative to Apple’s baked-in offering. Free, for iOS devices.