Looks like this tool also includes a "time bar" view that's in fact what Hipmunk was based off.
Also looks like they're building a successor to Hipmunk called Flight Penguin: https://flightpenguin.com/
Also looks like they're building a successor to Hipmunk called Flight Penguin: https://flightpenguin.com/
[and yes… that was why we went with a sub model over pay per use]