Hi. I want to know that how can i build a voice controlled 3 digit calculator. I want to use sd card reader module, arduino uno, speaker, hc 05. I will use speec recognition app to give input. Like, if i say 1+2, it should tell 3 from the speaker. I think i have to store sounds from 1 to 100 in sd card.
Hi,
What speech recognition app?
I think you will find the Arduino does not have the speed or program memory to do what you are asking.
If you get a PC to do it all, the Arduino can do the digit display, but then the PC has a perfectly good display.
Tom... 
Speech recognition app in the sense tat i have made an app using mit app inventor tat use google's speech recognition software to convert my voice into text and sends it to the Bluetooth connected to the arduino. You are telling tat arduino doesn't have the power to calculate. However I saw many videos of calculator made from arduino. They use button and lcd
Hi,
If you have the app working then, yes you could get the Arduino to do the maths.
It would be up to you as to how you organised a protocol to send the commands to the Arduino.
How you get the Arduino to speak is another thing.
You need to do some google research.
Tom...
I think that i should ask this question in the programming forum
I think that until you have some explicit programming questions, you should leave it here.