I have an application on my iPhone that collects and appends data into a CSV files, and has two options for the storage of said files:

A) Local storage on the phone

B) Cloud-based storage on iCloud

I'd like to write a client-side script in JavaScript that processes the data points in these CSV's (and puts them onto a chart with Charts.js), but I can't find a way to access the file.

Is there some kind of API that can provide these options? Any help is much appreciated :)

Thank you all in advance,

Peter