The Modest iOS Store was a multi-tenant, white label application that our merchants could easily adopt as a standalone app or as an SDK that could attach a storefront to their existing iOS app. When Modest was still young, and was "all-hands-on-deck," I got to do a bit of iOS development consuming the Modest APIs and rendering UIs.
The PREIT iPhone app was a small, marketing and informational application for each of the company's 30-40 shopping malls. The application used your phone's current location to find their nearest mall, give information about the mall, store directories, SVG based maps, calendars of events, etc. One other engineer and I created an API for our Rails-based CMS and then built most of the native Objective-C iOS app prior to me leaving the company... at which point a 3rd party contractor finished and "polished" the application