Bookmarking Tool for Web Design Inspirations

Hi,

The idea simply is an app that takes a link for a web page, then spits out the following:

• Screenshots of different sizes (Desktop, Tablet, Mobile, etc...).
• Full color palette .
• Fonts used in the page.

Then all those information (+ notes) can be saved and organized in collections for later reference for inspiration.

This is my first foray, and I'm currently stuck and not sure how to validate the idea! Any help is much appreciated.

Thanks