I'm building an app and one of it's features will be the calculation of profit and loss. I want this to be applicable to most major market indexes from equities, to futures to currencies, etc. So, is there some sort of API that I can use that would import the data and when a user enters the entry and exit price, it calculates their P&L? Without me having to manually key in every tick value per instrument.
Depending on which broker you use you might be able to get that instrument information via their API. For example: with IBKR you can request so-called contract information.
That simple, huh? Here I was thinking that I'd have to go through some independent dealer in API data.
Cool, it's called a "portfolio manager" and the one I worked on had 100s of developers work on it for 10+ years and still didn't do all that, so good luck!
I get all of that.... But, I've come a long way since posting this. It turned out to be simpler than what I thought from the front-end but it's the back-end that's gonna be an issue.