There have been NUMEROUS apps that provide beefed-up searching (multi-city,etc.) for CraigsList. Most get in trouble with CL because they're violating CL's TOS.
Craig and Company want you on their site, not on an aggregation site that sucks their listings...so they shut aggregators and scrapers down pretty quickly. OLX is, if I recall correctly, one of the many companies that has already gotten in trouble for doing this.
Craig and Company want you on their site, not on an aggregation site that sucks their listings...so they shut aggregators and scrapers down pretty quickly. OLX is, if I recall correctly, one of the many companies that has already gotten in trouble for doing this.