MapBox is a suite of open source mapping tools. The MapBox iOS SDK can be used to create interactive map-driven applications for iOS devices. It also allows users to host their maps so that they can be embedded on webpages and shared with a wider audience. All maps created using MapBox are compatible with Android and iOS devices.
MapQuest's recent entree into mobile developer tools is an interesting one. Choosing Android over iPhone means going toe to toe with Google, a familiar competitor to MapQuest on the mapping front. Mapping is logically MapQuest's turf. The company was helping people find directions online before Larry and Sergey were even in graduate school, let alone leaving to found Google. Of course, another way of looking at it is that Android is in line with MapQuest's latest push to open up mapping data.
Mobile phones and an increasing interest in location on the web have fueled a number of coupon and deal websites. Each seems gunning to be the site for local specials, albeit with a slightly different angle. And another thing in common? They usually have an API.