It's reasonably beyond doubt that mobile is where most people will access information online - including classifieds. I understand Craigslist was founded on the desktop web however my question is; why do they still not have a native app for mobile? Is this due to resource, or perhaps a business or philosophical choice?

Ebay appear to have revived their marketplace businesses with Ebay.com, Gumtree etc on mobile. Personally in regards to ecommerce, I much prefer mobile to the desktop experience.