After iPhoto landed on iOS in March, people quickly discovered the app used OpenStreetMap data for the map tiles. At the time, there was no attribution given to OSM but that has changed in the latest version of iPhoto, which was released earlier this week. OpenStreetMap pointed out in a tweet that Apple now lists OpenStreetMap contributors in the long list of acknowledgements for the app.
Richard Fairhurst, OpenStreetMap Foundation board member, explains how the foundation nudged Apple to get the attribution added to iPhoto,
The OSM Foundation has made informal contact with staff at Apple and, in addition, one of our volunteer mappers who is an iOS developer spoke to people at Apple. We believe it was the latter that precipitated adding the attribution - it's great to have such an active and engaged community!
OpenStreetMap is a crowdsourced mapping platform that provides free map data in exchange for an attribution. Both FourSquare and Wikipedia use OSM data in their apps.