Note: Continued use of GPS running in the background can dramatically decrease battery life.
Track and log your bicycle rides. You can use this application either "stand-alone" or you can optionally upload your ridelogs to a website. This app enables you to log just your date and distance or track and map your ride with the iPhone GPS. You can then share your ride on Facebook or Twitter, or eMail the resulting GPX file to yourself.
If you choose to upload your ridelogs to the Ridelogs website, you can further manage your bicycling activities, such as associating what bicycle you used, adding additional detail, analyzing your distances by week, month or year or viewing your rides on a calendar. The weather at the time and location of your ride is also automatically associated with your log!