User Ideas
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Calculate hours, mins, secs...
Add the ability to calculate time together i.e. 30 (minutes)+ 33+ 1 hour 12 + 45 + 6 + 5 hour 23= X hours and X minutes
12 votesFunction URL Encoding Corrections:
We are looking into this for a future release, in the meantime please use a custom function whenever more convenient:
calc://action?addFunc=hm~~%241%20%2B%20%242%2F60
This will allow to compute hours and minutes this way: hm(1;50) + hm(1;10) … however, it will always return minutes as a fraction of the hour.
For that, another custom function can be added so that hhmm(x) >> hhmm(1.75) = 1.45 and so on : calc://action?addFunc=hhmm~~floor%28%241%29%20%2B%20%28%241%20%20floor%28%241%29%29%20%C3%97%2060%2F100
Please note, both functions must to be used separately since the current release of CALC does not yet support nested custom functions.
p.s. tapping the calc:// links on your device should add the function to the custom advanced function section of your CALC app.

View multiple lines of history setting
Without having to touch again and again, it would be super ideal to view previous lines of calculations, and copy values to present calculations.
I see that users may view previous calculations in history, but there is no option to view a certain number of lines of history WHILE calculating. This function on physical calculators is priceless, and feels limiting to use an advanced iOS without the capability.
3 votesUsers have the ability to use the tape roll or side by side history in the Landscape mode. Portrait mode history is now under consideration – suggestions welcome!

Division improvements
1. It would be nice to isolate operations with a horizontal line that separates the numerator and denominator, like the n/d function on TI and Casio calcs
2. The division symbol feels more mathematical with a rising slash( / ) instead of a horizontal line with dots, which is really an arithmetic symbol, not a math symbol, and just confuses people; see YouTube viral video of 6 ÷ 2 (1+3)
For a solution, simply use the forward slash, or even better, also allow a n/d function with numerator and denominator, to simplify dimensional analysis for physics and chemistry
THANKS FOR…
1 voteCALC allows to use the rising slash (/) instead of the division symbol via two options:
1.) tap and hold the division button to create 1/x
2.) doubletap the division button to use the slash instead
We are currently evaluating the option to allow switching the default division button for a slash via settings. 
Hex need ability to put in af
Need the ability to use values a through f in the hex mode ... To insert af for the custom hex function, currently you'd need to use the advanced edit mode in CALC. Just tap and hold the answer area to activate or tap and select the option from the popup menu. We will review how to make this process better in a future release :)
1 voteTo insert af for the custom hex function, currently you’d need to use the advanced edit mode in CALC. Just tap and hold the answer area to activate or tap and select the option from the popup menu. We will review how to make this process better in a future release :)

Do calc AFTER you press function
This is the only thing that keeps me from using the app more. It is soooooo strange that the answer is shown with partial entries. If is very confusing. Please have option to wait for the next function key before showing an answer.
7 votesThis is actually one of the main benefits of CALC, – it will calculate as you type, so you do not need to press = at all unless you’d like to store and use the expression or the answer. There is no way to determine at what point a calculation should start and stop, but if we get enough votes on this, we can add the ability to turn the “live” feature of CALC on/off to make it work like a traditional calculator…

Make it more obvious how to do Negative Numbers
Negative numbers are produced by just typing the minus "" before the number or by tapping and holding the minus button afterwards, but since there is no "+/" button it is not immediately obvious how this works.
7 votesConsidering adding an initial hint on the negative button to resolve this.

8 votes
Reviewing feasibility for the next update v3.5.1
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