Thanks for taking time and going over the project!
Actually regarding using library for eval() calls, I wanted to keep the project vanilla/ with least libraries as possible.
Also, one query I have that is can we pass html entities to functions? For reference, in Button.js component, for multiply and divide (and all operator) buttons I have used html entities to display the respective symbols for them. But I also want those symbol on the calculator display (for multiply and divide). But I am not sure how to pass the html entities for those symbols through the function to Button component. So I have passed strings - *, / for multiply, divide respectively. Do you got any idea regarding this?