Originally Posted by
Aliquot
What did the Matrix App do that the website doesn't?
The website is great for a desktop browser, but terrible to use on a mobile phone. That is the main issue here.
But since you asked:
The app allowed to bookmark specific itineraries, and then update all bookmarked itineraries, to see how prices had changed and if those itineraries were still available. I don't see that on the ITA Matrix website.
The app kept a longer search history.
You could use your location to suggest airports (which I never used).
Departure and arrival times settings were more flexible in the app.
In the app, you could enable/disable mutli-airline flights.
There were additional, smaller differences. The search window could be 5 weeks, and the search results were often different. I found itineraries with the app that the website did not deliver - unless you already knew exactly what you were looking for. I think the app had a somewhat longer timeout setting in the search algorithm. I scored some amazing deals or itineraries that way.