Convert is a very useful iPhone application made by TapTapTap which converts just about any unit of measurement for you in an instant. It has an amazing user Interface, also not to mention very easy to use, and it has an actual calculator if you need to do some math.

Some issues: While this app is extremely useful and has a great User Interface, it lags a lot and sometimes it takes up to 15-20 seconds if you type in numbers to be converted to show and convert. After a while using it however, it stops lagging and runs pretty fine.

This application is $0.99, highly recommended.

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