Yes,its free

Yes , you can

Materialized color scheme is used in Aione Framework

No, It's not. There are many framwworks which are of 12 column grid systems but AioneFramework is 100 Column Grid System

A Progressive Web App (PWA) is a web app that uses modern web capabilities to deliver an app-like experience to users. ... You can deploy your app as a PWA as well as Native app and take advantage of both channels.

noo

A service worker is a script that your browser runs in the background, separate from a web page, opening the door to features that don't need a web page or user interaction. ... Before service worker, there was one other API that gave users an offline experience on the web called AppCache.

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