There are two calculator apps on the Kindle that are good, and have their respective strengths and weaknesses.
For this post, I will focus on Calculator, by 7 Dragons. It is easy to see. The graphics are good, and large enough for someone who has vision loss. It took me a minute to figure out that there are keyboard shortcuts for the mathematical symbols such as add, subtract, sine, cosine, etc.
This app gives you more than the basic calculator because it includes the trigonometric functions: sine, cosine, tangent, etc. Not sure who uses these besides students and mathematicians, but they’re there for use for whoever needs it.
Comparing this app to Mobigloo’s Easy Calculator App, Calculator has an easier keyboard set up. The keys on the calculator are easier to see and are white with black letters. So they have better contrast than Easy Calculator’s grey, and smaller keys.
The thing I like better about Easy Calculator is that you can see the whole transaction like it is written on a piece of paper. So, when you do 5×5, it shows that, and puts a line underneath it to show the answer. This is good because that way, you can make sure you put in the right numbers.
Both apps include a history button. Hitting the enter key on the Kindle is the “equal” key on the calculator for both apps. That is an obvious choice.
Overall, Calculator is definitely not as fast as punching keys on a regular calculator, but compared to a computer version, it is much more portable. It is good to not have to carry so many little gadgets in my purse because I can just access it on my Kindle whenever I need it.
“It provides all kinds of operations of a normal calculator an even some of the more advances “scientific ones” like trigonometric functions, exponents, roots, 1/X, etc. It’s very user friendly and the redesigned keyboard layout for typing numbers works pretty well and lets the user input numbers much faster and more easily than with the standard Alt+Letter or Sym key.
It has memory functions very well implemented and supports seeing history of the last 10 operations and values stored in memory. I find that really useful. “