It's broken because the people who go out of their way to create software for craigslist aren't largely duplicating functionality.
Want a map view so you can see all the relevant listings in one view?
Want craigslist to deliberately filter the same text or picture used for different listed apartments or jobs so you don't waste your time or get scammed?
Want to search by squarefoot or by actual bedrooms or by picture?
Apple would say "There's an app for that." Craigslist says "screw you".
Have you ever heard of the network effect? Craigslist has such a lock on its market that you would have to have something extremely compelling to dislodge them. A few flashy maps and a web 2.0ish appearance wouldn't be nearly enough to do it.
Classified sites gain a regional dominance. Craigslist in canada for example, is only really dominant in vancouver, one of their biggest foreign markets. Kijiji is dominant in other towns.
Want a map view so you can see all the relevant listings in one view?
Want craigslist to deliberately filter the same text or picture used for different listed apartments or jobs so you don't waste your time or get scammed?
Want to search by squarefoot or by actual bedrooms or by picture?
Apple would say "There's an app for that." Craigslist says "screw you".