Download & Parse File that Describes a 3D Environment on iOS/Android

I intend to create a Unity3D application(Android & iOS) that renders 3d environments for surveyors. They will be able to view and navigate a 3d version of a development site by dragging.

To render a 3d environment; the application will download & read a file that contains a list of x,y,z points and translate those into a 3d environment.

My Question 1: Are there Unity3D functions/ways to download a file from the internet on iOS and Android? Does Unity3D currently handle/interface with the native OS file handling(reading, writing, saving)?

My Question 2: Can I write the whole project in C# and still compile the project for both Android and iOS? Also is it true(I think I read somewhere) that you cannot use Unity3D Javascript scripts for Android?

If not, is there another way you think I could get the file onto the Smart Phone/iPad except for combining it in the app resources(or is that my only solution)? Maybe I can write native plugins to download, save and parse files?

A1. Use the WWW class to fetch an XML file (or text file) from a server.

A2. Yes. Javascript will work on Android, though.

Note that you will need to write code that converts the xyz data from the text file into a 3d model that Unity can display. See http://unity3d.com/support/documentation/ScriptReference/Mesh.html.