- Export your app using Xcode's Organizer, be sure and choose Save for Ad Hoc Deployment
- Create a folder on Dropbox and add your app's .ipa file
- Add app.plist to your folder with the following contents:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">