Apple id

Only persons age 13 years or older can create accounts > iTUNES STORE - TERMS AND CONDITIONS

She can share yours or your wife's, but if you purchase anything for your daughter, you cannot transfer it to her Apple ID whenever she gets one. I do not recommend removing a passcode nor telling your daughter what the passcode is. That is your only way of keeping track of her usage and setting Parental Controls.

You can use whichever Apple Id you want. Or get her her own if you want to. Or do a combination of both such as Your Apple ID for iTunes and apple Store so she can access your purchases, and her own for Messages and FaceTime so she does not get your messages or calls. Or just turn them off.

It really comes down to how you want to manage it. Personally I'd set it up with your or your wife's Apple ID. At 3 years old its not like she'll have people messaging her or calling her.

You can also turn of the Passcode in Settings->Passcode->Turn Passcode Off

You can turn off automatic downloads on your devices you don't get her apps and games.

Beyond that, you can totally create a new Apple Id you control for it. There's nothing to stop you from doing that. With whichever email address you have now.

She could then in the future use that as her own, and change the email address to her own.

This mostly applies to two people, but it is easily extended to more than two.

Using More than One iDevice on the Same Computer

This applies mainly to couples who are adding another device and do not want their email, messages, etc. being duplicated on both devices. To begin read: How to use multiple iPhone, iPad, or iPod devices with one computer. You need to establish a separate Apple ID and password for whomever will use the new iDevice. See Apple - My Apple ID and Frequently asked questions about Apple ID. The easiest way is to do this on the computer using iTunes: iTunes- How to set up an Apple ID within iTunes.

On the computer create a new user account for the person with the new iDevice. This will be the user account that person will always use. He/She will no longer use the other user account. This way that person will have a separate iTunes Library. Note that once done you cannot "share" apps under a single Apple ID. Each of you must purchase your own apps under your own Apple ID. When you decide to split up like this one of you will need to re-purchase the apps that they want to use.

Start by transferring the new device(s) to a new account along with all your data. Save any photo stream photos that you want to keep to your camera roll (unless they are already in the camera roll) by opening your Photos app, tap on Albums icon at the bottom. Now, tap on My Photo Stream album; tap Select; tap on the photos you want to select;, tap the share icon (box with upward facing arrow) in the lower left corner; then tap Save to Camera Roll.

If you are syncing notes with iCloud that you want to keep then you need to open each of your notes and email them to yourself. Later you can copy and paste the text into new notes created in your new account.

Tap on Settings > iCloud > Delete Account (only deletes it from this device, not from iCloud; the person keeping the current account will not be affected,) provide the password to turn off Find My Phone and choose Keep on My iDevice when prompted. Sign in with a different Apple ID to create your new account. Choose Merge to upload your data.

Once you are on separate accounts, you can each go to icloud.com and delete the other person's data from your account.

Note: The essence of the above was created by user, randers4. I

have made substantial changes to improve readability and syntax.