Android App Review: CALCU: The Ultimate Calculator

Ask Mrs. The Droid Lawyer what my only flaw is and she’ll laugh hysterically at the thought of only one flaw say, “Math.” Yes, complex math problems puzzle The Droid Lawyer — confession: I didn’t learn how to divide until college, and I can’t do long division; forget about some complex geometry question. This common meme might describe how I feel about math education:

Calculators Needed, Not!

My math deficiency doesn’t mean I don’t know how to complete the problems, I just prefer a calculator, as opposed to working the equations out on paper. Actually, I love calculators.

A simple, but efficient calculator

Here’s how the developer pitched his app, CALCU: The Ultimate Calculator (free):

We just released a simple, yet beautiful and powerful calculator in which we focus mainly on UX [user experience]: gestures for additional features that users might want to access repeatedly, swipe down the keypad to perform calculation, or swipe up to clear all.

Honestly, the pitch wasn’t all that appealing. Really, the app sounded more gimmicky than functionable. Because it was free, I figured I could download, install, and use the app, and if it flopped, all I wasted was a little time. Of course, since there’s a post, the app must be worthwhile.

CALCU certainly lives up to its claim, though I’m more enamored with the design than the swipe functions. Don’t misunderstand, the swipe is cool, but the design is beautiful, efficient. CALCU comes with a number of different ways to theme your calculator, including the aesthetically pleasing iOS-style.

CALCU iOS calculator theme

I know I said not to make your Android look like an Apple, but we’ll break that rule this one time. Plus, it’s only one app, not your entire device. If you’re a purist, just stick with the default theme, it’s beautiful, too.

CALCU Calculator page


CALCU kills the competition (at least the apps I’ve used) with its ability to customize certain keys on the keyboard. Even though the default keyboard is minimalist by design, CALCU offers additional mathematical functions with a smooth swipe up the screen.

CALCU bottom functions

If you want even more functions, simply swipe a second time to reveal the “add keys” menu for two more rows of functions.

CALCU reset or add keys

Pressing a “+” button gets you a menu to add an operator (sin, cos, tan, etc):

CALCU operator

Or a constant, where you can select your own constant number, or one of the many built-in mathematical functions:

CALCU extra calculations

The ability to add more function keys expands CALCU’s range of operations without diminishing the minimalist nature of the app.

Full swiping

The CALCU developers are most happy about the addition of swiping functionality. As I mentioned, I’m not totally enamored with the function, but it’s a nice feature to have.

You can enable swipe by going to Menu > Labs and clicking the check boxes next to Swipe to perform calculation and Swipe to clear.

CALCU labs

Restart the app — I suggest you clear it from your back menu — and you’re ready to use the functions. Simply swipe down on the keyboard to run the calculation:

CALCU swipe down to calculate

Remember, swipe on the keyboard, otherwise you won’t be able to set the calculation — I got confused with this a couple of times. Also, even though you see the final number, the calculation didn’t technically finish until you hit equals (or release your swipe).

Similarly, you can view your history of calculations (like a tape on a calculator) by swiping down on the display.

CALCU calculator ribbon

Touch is crucial for both functions. You can clear your calculator history by clicking the “notifications” button on the lower left.

CALCU clear ribbon

How do I make a negative number?

CALCU seems to omit the “+/-” button used to make a negative number. Of course, you’ll find the button on the “Constant” screen, but nowhere else.

CALCU constant button

This confused and frustrated me, until I discovered that the minus sign acts as the negative number.

CALCU negative number calculation

 The developer tells me that this saves one extra button (keeping with the minimalist design) and still maintains the integrity of the functions with the merged key.

But is a calculator necessary? And other lasting impressions

CALCU is a great looking app, and one of the best calculators I’ve seen. Unfortunately, with the improvements in Google Now, and especially the integration of Google Experience Launcher, I’m not sure I even need a calculator.

Google Now calculator

I can simply speak an equation, and Google will send me the information. That said, Google Now’s admittedly limited in its ability to perform more complex calculations.

I really like that CALCU is free, and that any advertisements are placed tastefully off the main screen. CALCU does offer an in-app purchase option, which will remove the ads for $2.05. As always, I encourage you to support developers of great apps, and $2.05 isn’t that much.

For being a robust calculator, CALCU is missing a fractions button commonly found on other scientific calculators. I’d also like to see the ability to go back and edit a line on the ticker tape, in case you make an error.

Overall, I think CALCU is a great replacement for Android’s stock calculator, but still lacks some of the more powerful functions of apps like RealCalc Scientific Calculator. I think most attorneys will benefit from CALCU’s enhancements, and probably won’t notice many missing function keys.

I’m giving CALCU: The Ultimate Calculator 4.5 of 5 stars.

Get this app on Google Play


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Jeff Taylor

I’m just an ordinary guy living an extraordinary life. I’m also an attorney and I blog about Android for lawyers. You can follow me on Twitter, LinkedIn, YouTube, or Google+.