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  1. Open the *.xcodeproj file in Xcode.
  2. Add your Apple ID to Xcode settings → Accounts. Make sure that you add/generate a ’signing identity’.
  3. Click on the project on the left side and make sure that the ‘target’ in the middle column is code-signed with your Apple ID.
  4. Plug in your iPhone and wait until it is configured (it will appear at the top).
  5. Press on the play button.
This assumes that there are no dependencies that you need to install and that there are no build errors.
 
  1. Open the *.xcodeproj file in Xcode.
  2. Add your Apple ID to Xcode settings → Accounts. Make sure that you add/generate a ’signing identity’.
  3. Click on the project on the left side and make sure that the ‘target’ in the middle column is code-signed with your Apple ID.
  4. Plug in your iPhone and wait until it is configured (it will appear at the top).
  5. Press on the play button.
This assumes that there are no dependencies that you need to install and that there are no build errors.

I need to build it into a .app as I am following this tutorial:
 
As I said, you have to build it first, using Xcode. In Xcode there is a product area. The actual application will be put in ~/Library/Developer, after it was built.
 
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