"UnitConverter Pro" is the best and most sophisticated unit converter for iOS. It covers 649 units from 56 categories used by various users from students to engineers in their daily life or scientific/engineering calculation. Multiple units like feet + inch are also supported.

◆◆ Simple and Speedy User Interface ◆◆
Only two taps to get a required unit conversion table! (1) Tap desired unit category in category list and (2) tap value field of any unit you want to convert from. Immediately, converted values are displayed for all the other units based on "1.0" of the unit you tapped.

When you want to input arbitrary figure, tap the value field one more time to display a numerical keypad, which is specialized for input numbers including exponential expression.

◆◆ Functional digital display ◆◆
Converted values are rounded with user-specified decimal place and delimiting every three digits with comma. You can change decimal place from 1st to 9th any time.

◆◆ Search for a unit ◆◆
Copy & paste unknown units as well as numbers you find in internet or papers. UnitConverter Pro searches the unit from all the implemented units and show you a converted value immediately.

◆◆ Copy and Paste ◆◆
Double tapping a unit label allows you to copy converted value or to input figure by paste.

◆◆ "Favorites" category ◆◆
You can create your custom page in "Favorites" category by registering any units from any categories.

◆◆ Customization of category and unit list ◆◆
User preference screen allows you to customize the category list as well as unit list by eliminating unnecessary categories and units.

◆◆ Optional selection for Calorie/BTU definition ◆◆
There exists several definition commonly used for Calorie/BTU calculation. User preference screen allows you to specify the definition used in the conversion from the following list:
- Thermochemical Calorie
- International Table Calorie (14.5℃ Calorie)
- 15℃ Calorie

== Category List for Ver.2.3 ==
◆ Lengh-related : Length / Area / Volume / Velocity / Acceleration / Diffusion Coefficient / Volume Flow Rate / Specific Fuel Consumption

◆ Mass-related : Weight / Mass Flow Rate / Density / Specific Volume / Mass Velocity / API Gravity

◆ Power-related : Power / Surface Tension / Pressure / Viscosity / Kinetic Viscosity

◆ Heat/Energy-related : Energy / Power / Heat Flow / Heat Flux/ Heat Relieving Rate / Specific Enthalpy / Mol. Specific Enthalpy / Specific Heat / Mol. Specific Heat / Thermal Conductivity / Heat Transfer Rate / Fouling Resistance / Torque / Gas Calorific Value

◆ Light-related : Luminance / Illuminance / Luminous Flux

◆ Electromagnetic-related : Magnetic Flux / Magnetic Flux Density / Radioactivity / Exposure Dose / Electric Current / Electric Charge / Voltage / Electric Resistance / Electric Conductivity / Electrostatic Capacitance

◆ Others : Time / Temperature / Angle / Molecular Number / Mole Flow Rate / Mol. Concentration / Blood Sugar Level / Spectroscopy / Concentration / Data Size / Data Rate