Engineering Unit Converter

This is a comprehensive engineering unit converter with an intuitive spinning wheel interface. There is no ad, no hidden code, no need for a network connection, and the total size is about half a megabyte.
Choose a category such as length, energy, entropy, electric charge, etc., from a list. The available units appear in two spinning wheels. Spin the wheels to select 'From Unit' and 'To Unit'. That is it. You can change the input value in the yellow field, sort units, or use the swap button. Additional info about a measure is displayed when the help button is pressed.
If you find a particular measure or unit is missing, just write to us. We will update the converter in no time and dedicate the release in your honor.
Some of the features of the Converter Plus (an upgrade of this Converter) includes:
1. Lightweight: It is a very small app (about half a megabyte) with very little footprint.
2. Does not require access to the net.
3. No advertisement or any other promotion.
4. User input driven: When users asks for a new measure or a new unit, the app is quickly modified.
5. It has a unique spinning wheel design (as far as we know the only interface of this type). Most users love this (but some do not). It requires minimum number of clicks for a unit to be converted.
6. Also, while rolling the spinners, users have a better feel for the available units when compared to a drop down selection menu.
7. Although the front page looks cluttered with what seems like too many measures, once a particular measure is selected, the interface becomes more interesting. User can change the measure from a selection menu instead of returning to the home page.
8. Various levels of customization: A measure can be added to or deleted from the favorite tab. Once a measure is declared favorite, units can be sorted alphabetically or by value by selecting sort command from the Customize menu. Unwanted units can be deleted by simply aligning the wheels for the undesired unit and clicking the delete button. New unit or even new measures can be added.
9. Frequently used top ten measures are dynamically listed in the Frequent tab.
10. Compound units: Sometime units need to be converted to compound units, e.g, converting meter to yard, ft, and inches or vice versa. All you need to do for that is select Length, then 'm' on the left spinner and 'yd ft in' on the right. Similarly converting 'seconds' to 'hour min sec' is more meaningful than to hours with many decimal places.
11. The swap button makes it possible to quickly reverse the left and right units, thus reducing unnecessary spinning.
12. Expression evaluation: Sometimes engineers need to calculate a value before converting units. For example, the floor of a room is measured as 17 ft by 23 ft and you want to find the area in sq. m. In that case type in 17*23 on the from unit box and click the update button.
13. The info button on each unit gives unit specific help, the engineering dimension of the unit, and also displays detailed results when applicable. For example when calculating mortgage interest (Interest & Mortgage), the amortization table is displayed in the info page.
14. When calculating interest the principal, interest rate, and number of years can all be user specified. To avoid complicated interface, the three numbers (after variable interest and period are selected on the spinner) are typed in with white space separating them. To make the input field larger, the phone has to be simply tilted to landscape mode.
15. The converter goes much beyond traditional engineering measure. Beside mortgage calculation, it can do radix conversion, display physical constant, and UTM (latitude longitude) coordinates conversion. The latest measure is valuable to mariners (and even fire fighters).