Replace device ID iphone what is it

Apple ID explained

Halyna Kubiv

In Apple's universe, everything and everyone is clearly identified: Apple distributes the so-called UDIDs for the individual iOS devices, and a digital account is provided for each user - the Apple ID

In order for the data exchange between the devices to function smoothly, the user should register with a unique ID - the Apple ID. This identification can now be used in the iTunes Store and in iCloud, registration takes place either via iTunes or Basically, you can differentiate between two large areas such as media and personal data - no common Apple ID is necessary for this, you can also use two different ones as required. The iTunes Store is responsible for media such as music, films, TV shows, books and apps, and all of its variants such as the App Store, Mac App Store, iBook Store - all use the same Apple ID. Data synchronized iCloud: mails, contacts, calendar, reminders, notes, photo stream, documents and backups.

In addition to these two large areas, various apps under iOS and OS X use an Apple ID, which you specify during the initial configuration; it is independent of the existing iTunes ID and iCloud ID, you can theoretically enter a new Apple ID, which increases but only the effort. Such apps include iMessages, Facetime, and the Game Center. Apple lists all of the services that require an Apple ID in its knowledge base article. (Knowledge base article HT5616). We therefore recommend first of all to differentiate between media and data for each individual user and to use one of the two IDs for the apps. Of course, the same Apple ID can also be used for all areas.

Applications each with the same Apple ID

Applications with an independent Apple ID

Apple ID (iTunes)

Apple ID (iCloud)

Face time

iTunes Store


Game Center

App Store



iBook Store


Mac App Store

iTunes Match


iTunes Home Sharing


Safari (bookmarks etc)

iTunes U




Documents and data

iPhone Search


Components of an Apple ID

The user only needs an email address - Apple assigns one with the domain @ when registering via - and a password that is as secure as possible. This should be at least eight characters long and contain at least one uppercase letter, one lowercase letter and one number. Apple IDs are quick to create and since the free iCloud has replaced the paid Mobile Me, they are also easily available in larger numbers. When using Apple IDs with Apple's services, however, there are a few things to consider.

Since most users also have their credit card details on file with the Apple ID for iTunes, it is particularly important to choose a secure password. The password length is not limited to eight characters, i.e. you can also think of a longer character string. The easiest way for the human brain to remember the cryptic sequence, but rather conclusive statements such as "4 fish swimming pool". In addition, such sentences are more difficult to guess than your own date of birth or the names of family members.

What is bound to an Apple ID?

All content purchased from the iTunes Store is associated with an Apple ID. Unfortunately, there is no way to merge two Apple IDs with their purchased content. The synchronization of personal data via iCloud works via the account, which can be accessed from any number of computers. The devices, on the other hand, be it a Mac, iPad or iPhone, do not necessarily have an Apple ID connection. The only catch: iTunes requires the respective computer to be authorized for the content purchased.

How many devices can you authorize with an Apple ID (iTunes)?

In its iTunes usage guidelines, Apple points out that most content that has already been purchased can be downloaded again on ten devices. No more than five computers (desktop or laptop, Mac or Windows) may be activated at the same time among these devices. In contrast, it is entirely possible to use the same ID to authorize three computers and six iOS devices, for example. Authorization means nothing else than that the user logs on to the new device with the Apple ID for iTunes and the corresponding password. In the desktop version of iTunes you also select the option "Store - Activate this computer ..." An overview of all activated devices can be found in the account information under "Store - View account".

EnlargeAn overview of all devices that are connected to the respective Apple ID for iTunes can be found in iTunes - Store - View Account - iTunes in the Cloud - Manage Devices.

The limitation according to the number of devices only applies in connection with content purchased in iTunes, other applications such as iCloud-enabled apps can theoretically be used on any number of devices at the same time. You don't have to activate the computer for this. Apple TV has a special position in this regulation. From Apple's point of view, an Apple TV is not on this list.

1 device

5 devices

10 devices, including a maximum of 5 computers


Rented Films


In-app purchases (consumable)




Movies, TV shows (purchased)


Auto download music, apps


iTunes Match


iOS apps


Mac apps


iTunes Plus Songs


Note: The restrictions on simultaneous use of iTunes content apply to private use.