Alongside the Google Maps Wikipedia layer and our iOS nearby articles feature (correct?), the Android/iOS app Geoloqi now has a Wikipedia layer. 

More info:

Geoloqi is pretty cool. It has some cool geo features you can tack on to your apps too: in addition to its own feature set. (If anybody wants a contact, I know the founders.)

Steven Walling
Community Organizer at Wikimedia Foundation