Devices

Why Device Management Matters

In development and Ad Hoc distribution, profiles must specify “which real devices may install”. The Devices list is where you maintain these devices:

• Development profile: development certificate + App ID + devices.
• Ad Hoc profile: distribution certificate + App ID + devices, for distribution outside App Store / TestFlight.

Getting a UDID

The UDID is a unique hardware identifier for each iPhone/iPad. Ways to obtain it:

• Finder: connect the device → click the device name → view “UDID”.
• Xcode: Window → Devices and Simulators → select the device.
• Command line: idevice_id -l (requires libimobiledevice).
• Third-party “UDID finder” pages: open on the device to display and copy.

Adding a Device

1. In Certificates, Identifiers & Profiles → Devices → ”+”.
2. Enter a device name (e.g. John iPhone 15) and the UDID.
3. Save; the device can then be referenced by new Development / Ad Hoc profiles.

Device Limits & Maintenance

• Annual limit: each team can register a limited number of iOS devices per year (usually by device type, e.g. 100).
• Deleting does not immediately free slots: removed devices don’t return their slot until the next annual reset.
• Suggestion: register only active test devices, clean up quarterly; re-add necessary devices after the annual reset.

Self-Check List

• UDID obtained reliably (copied, not typed)
• Active test devices registered with name and UDID
• Development / Ad Hoc profiles include the target devices
• Device count monitored and cleaned up regularly

FAQ

• Ad Hoc build won’t install? Check whether the device UDID is in the profile; re-sign and reinstall.
• Device list “full”? Wait for the annual reset, or remove unused devices (note: removal doesn’t immediately free slots).
• Does TestFlight require device registration? No. TestFlight testers don’t need UDID registration.