I'm thinking of building a web app that helps people analyse their investments. Users would upload their mutual fund statement, and the tool would analyse it and give them some conclusions.
Since investment data is sensitive, some users would be hesitant to upload it to an unknown web site, so it would be good to provide an option for those users to download the app and run it locally.
How do I support this without building two apps? What if I code up everything in JS, and avoid any server-side code? Then I can provide a Download button that downloads a zipped HTML/CSS/JS file. Users can unzip it, double-click index.html and use the app. I could read the mutual fund statement using a File Open dialog box and the file API, without uploading it to a server.
Will this work? Are there other ways to achieve this? What are the pros and cons of each of these?
Requirements:
- Users should be able to use it as a web app without installing anything.
- Privacy-sensitive users should be able to download the app to their hard disc and run it locally, without any data being transmitted to a server.
- If needed, we can restrict support to only Chrome on Windows and OS X, dropping other browsers, other OSs, tablets and phones. This is just a hobby weekend project, which no one may even use.
- I don't have the time to build two apps, one a web app and another for downloading and installing locally.
