WeightTrack is the best weight monitoring and weightloss app for iOS.

Weight management is hard, and for some of us it's important. WeightTrack is a tool to facilitate weight management which is simple, quick - and everywhere.

It's key, free features are

◦ Graph of progress over time (on iPhone/iPod touch, rotate the device to horizontal to see the graph)
◦ Note what was good and bad about particular weigh ins.
◦ Understands and can use kilogrammes, pounds, and stones, as units of weight.
◦ No data lock in - get your records out of the App in an instant.

In addition these exciting features can be unlocked:

◦ iCloud sync
◦ Reminders
◦ Predictions
◦ BMI Scale & Summary Measures
◦ Averaging Line
◦ Trend Line

The averaging line eliminates natural day to day variation in your weight, and shows your true, underlying weight.

Predictions tell you when you're likely to hit your target.