From their site: HopStop is your city transit guide. We provide door-to-door subway and bus directions and maps for New York City. You can also search for places to eat, drink, sleep and see in the City Guide. Use the API to integrate mass-transit and walking directions into your own website.
The following is a list of SDKs from our SDK directory that matched your search term. Though your definition of an SDK may differ, in our world, we define SDKs as platform- specific tools for consuming existing APIs of the sort we list in our API directory. For example, the Ruby SDK for consuming the Twitter Ads API. If you think an SDK, API, or other asset is missing from our directory, be sure to check our guidelines for making contributions to ProgrammableWeb.