The mobile app needs significant improvement. It should be updated.
Also - the search functionality leaves a lot to be desired. When I type search words into your search box I don't directly find what I seek. But when I type the same words into Google and site:flyertalk it appears more easily. That shouldn't occur.
On a lesser note a few more emojis and a like button would be nice. But if you enhanced the two things above I'd be pretty happy.