Ewert Technologies Blog

I have recently purchased an iPod touch and plan to start developing some applications for it.  To help me get a feel of the way applications run on iPhones/iPods I have decided to download several applications and try them out.  Since I am spending some time trying out various applications, I've also decided to write some reviews about them.

For my first set of reviews, I will be look and Unit Conversion software.  These are handy tools that allow you to convert between different units such as inches to centimeters, feet to meters, etc.  This is especially handy when travelling to a country that uses different units that you are used.  For this review, I installed the following five applications (all free versions) from iPhone App Store:

1. Convert (Unit Converter by PBF)
2. MultiConvert
3. Converter Plus
4. Handy Convert
5. Convert Units for Free

Convert (Unit Converter by PBF): 2/5

The free version of this application only contains Area, Length and Mass measurements.  If you want more measurements you have to upgrade.    You also get reminded of the ugrade everytime you start, which gets a little annoying.

The UI looks sleek, but I found it a little confusing.  To switch measurements you have to click on a button near the top, which then shows a list of measurements at the bottom.  When selecting a measurment, two button under the display portion, show the default units for that measurment.  When one of the buttons are pressed, the list that used to show measurments now shows units to select from.  After selecting a unit, you click on the other button and select a differnet unit.  Values are enter by click on the display portion and using the number pad that gets dispalyed.

Because of the limited number of measurements and units, and the akwardness of the UI I only would rate this 2/5.

MultiConvert: 4/5

When starting MultiConvert, I was immediately impressed by the number of Measurements that could be converted (over 50) including basic things like: mass, length, speed, temperature, to obscure things like: Radioactivity, and Moments of Inertia.  This impressive list is presented in a table list.  Clicking on the Measurement brings up another screen with a long list of units that correspond to the measurement.  Along with each unit is a text field.  To make the conversion, simply find the you unit you want to convert from, enter the value and all the other units will be automatically calculated.

My one complaint of this application is, that while having a large number of units and measurements is good, it can be time consuming scrolling up and down lists to find the measurement and units.  For example when converting mass, if I want to convert pounds to kilograms, the pound unit is much further down the screen than the kilograms so I would constantly have to scroll back and forth.

One thing I would have liked was an easier way to copy the value.  To copy you have click on the text field, then select all the text and select the copy function.  Another think I would have like is to have some way to indicate which of the many units was the one I just entered, and to separate it from the ones that were calculated.  Overall, however, this is a pretty powerful application.

Converter Plus: (5/5)

Converter Plus looks and works very similar to MultiConvert.  At first I was disappointed, however, that it didn't have as many measurements or units as MultiConvert.  I then realized the power of Converter Plus; the main list of measurments, and each corresponding list of units can be edited.  New measurements and units can be displayed and re-ordered.  This gives all the choices of MultiConvert but lets you only display the measurements and units you really need so the lists don't get too long.

In addition to regular measurements, it also includes currency, tip calculator and a mortgage calculator.

Handy Convert: (4/5)

Handy convert uses spinners to manage conversions.  One spinner lets you choose the measurement, the next lets you choose the unit to convert from and the last spinner lets you choose the unit to convert to.  After setting the spinners you enter the value into the text field above and the conversion is displayed below it.

Having everything on one screen is nice, and allow for quicker conversions.  You are limited, however, to only seeing one conversion at a time.  Handy Convert also doesn't contain as many measurements and units as some of the other, but does contain the most common, such as Area, Lenght, Speed, Weight, etc. and even contains one for Cooking.

In addition to unit convertsion, it also contains a screen listing decimal - fraction info.  I'm not sure how often I would use that, but it could be handy.  Overall a decent unit conversion application.

Convert Units for Free: (3.5/5)

Convert units for free also uses spinners to handle selecting conversions.  This one only has spinners for the to and from units, and the measurement is selected from a pull up list.   What makes Convert Units different is that the unit value is edit within the spinner by typing on the ever present keyboard.  I found this a little awkward at first and found the spinners sometimes hard to use since you can accidently drag the display part instead of the spinner.

As for number of measurements and units, it isn't nearly as comprehensive of Multi-Convert and Convert Plus but like Handy Convert is has the basics.  Very simlar to Handy Convert but somehow I find the interface less appeally.

Summary:

If you want a comprehensive unit converter that will convert anything you want and more, go with Converter+.  If you want a more basic converter go with Handy Convert.