Is it a lot of pain to convert a website into a web application?

Question

HTML

The task is to make a measurer's calculator, into which the furniture catalog will be integrated and, possibly, a 2d / 3d layout of the premises should be generated later.
Since the company has corporate phones mainly on iOS and Windows, there is a decision to first make a web prototype of the application, and then transfer it to the Phonegap platform.
the question is how much time will it take for a cross-platform transfer?
and for one thing, tell me some kind of template for starting (maybe a yoman assembly or a boilerplate) and maybe you have come across some libraries for working with room measurements

Answer 1

everything is very simple -
your application-site must be self-sufficient - work without the Internet, saving data in local storage,
and when there is Internet - send and receive data from the server

Answer 2

a lot
of fungup still doesn't look like html

Answer 3

Create a webGL application if you are going to use 3D rendering. Then it's better to use cocoonjs instead of phonegap. The latter allows you to integrate webview into the application and thus run with full acceleration on all devices.
Check out here . Not quite on topic, but I think it's useful.