On iOS there are 4 types of builds and below are the differences between the four:
Simulator ad-hoc builds - these are software simulations of iPhones and Xcode would build directly to the simulator and QA testers / developers can test directly on their MacBook.
Ad hoc builds directly to device - with your iPhone connected to your MacBook, you can build directly onto the device with ad hoc provisioning - this would be considered a dev build. Conversely, if you're using Test Flight or Hockey App and a UDID is requested - this would be a dev build.
Enterprise provisioning onto device - with your iPhone connected to your MacBook, you can build directly onto the device with Enterprise provisioning - this would be considered a production build. This would apply to other services as well if you have Enterprise provisioning and it's distributed through Test Flight, Hockey app or Crashlytics.
App store build - these are builds that you're getting directly from the app store and would be considered a production build. Duh. ;)