When I installed google bar, I activated the translator, so when a website is in english, i move the mouse over a word and I get a tooltip with the word translated to spanish.
What I want to do is create an application like this, but instead of translating is going to multiply a number and give me the result in a tooltip.
Example. "the cup costs 24.99 usd", when I move the mouse over the 24.99, the tooltip would say "Pesos 374.85"
Do you have any idea where can I find information about this or how I should develop this?