Startup Idea: Offline Web Browsing History and Search Database App

Startup idea to develop an app that stores a user's web browsing and search history over the last few days, available in a searchable keyword database offline. The app is intended to help users access previously visited online content during periods without internet connectivity, catering particularly to daily commuters. The app can be monetized through ads or by offering an ad-free version for a fee.

Often I find myself on the train, as a daily commuter, lamenting the lack of access to cellular service on the train. I believe an excellent solution to something like this could be a piece of software (app) that stored the information my web browser loaded over the last few days or so (possibly self deleting to save space over time), all stored in a searchable keyword database available offline.

This way, notes, searches, and information I wanted to parse through that I had just spent the day researching or looking through would be available to me via this software. Monetizing could involve ads, or paying for the removal of them. As a designer who is constantly revisiting webpages of images and information, but often forget to screenshot or save the info, it would be great to be able to recover it in the short term during my commutes. I have tried, but there is nothing so specific. I haven't solved it, I simply do something else.