You will receive the five-digit transport PIN by post after you have applied for a new German ID card, residence permit or eID card for EU citizens. It is also called the activation PIN. To use the online ID card function, you must replace the five-digit transport PIN with a six-digit PIN of your own choice before using it for the first time. Once you have your five-digit transport PIN, you may use the AUTHADA app to set your private six-digit PIN for the first time.