Here's an app I've released earlier this month, Convert2Go
Convert2Go is an innovative unit and currency converter designed for easy and practical use.
It offers a wide range of categories and units to convert between, all from a single screen.
Moreover, Convert2Go is able to convert from and to mixed units.
* Over 400 units and currencies in 21 categories
* Built-in calculator
* Mixed units support : 1.93m can be converted to (and from) 6ft 3in
* Units / categories rarely used can be deactived
* Currency exchange rates updated on application launch
Version 1.1 brings
* Ability to send the last conversion by email.
* Sound feedback when a key is pressed.
* A new category : SI prefixes, with the following units : zepto, atto, femto, pico, nano, micro, milli, centi, deci, base, deka, heco, kilo, mega, giga, tera, peta, …
A 10-days trial is available
More information on the official website
Download it here