You need to sign in to iTunes 12 on your computer or the iTunes app on your iOS 8.3 device with your Apple ID before you can buy items from the iTunes Store or download your previously purchased content. To sign in to your iTunes account on the desktop version of iTunes, access the program's Sign In option. On your iOS device, however, use the iTunes and App Store section of the Settings menu to sign in to the iTunes app.
Open iTunes on your computer and click Sign In on the top menu bar to open the Sign In To The iTunes Store dialog box.
Enter your Apple ID credentials in the Apple ID and Password fields. Click the Sign In button to sign in to your iTunes account.
Confirm that you have signed in to your account; your name replaces Sign In on the menu bar. Click your name on the top menu bar to display the Account drop-down menu, which has options to manage your account.
Tap the Settings icon on the Home screen of your iOS device to open the Settings screen.
Select iTunes and App Stores from the list of options to open the iTunes and App Stores Settings screen.
Enter your Apple ID and password credentials and then tap Sign In to log in to your iTunes account.
Confirm that you have linked your iTunes account to the iTunes app; your Apple ID is displayed at the top of the screen. To sign out of your account, tap your Apple ID and then select Sign Out.
Tips & Warnings
- If you share your computer or iOS device, sign out of your iTunes account when you are finished using iTunes.
- To sign in to iTunes with a different account, sign out of the current account and then sign in with the new Apple ID account credentials.
- Use the iOS Restrictions feature to prevent another user from making purchases on your iTunes account. Open the "Settings" menu on your iOS device, tap "General" and then tap "Restrictions." Select "Enable Restrictions," set a pass code and then tap the iTunes Store switch to the "Off" position.
- You may be prompted by iTunes on your iOS device to enter your Apple ID password before you can download content.
- Apple: iPhone User Guide for iOS 8.3 Software
- Apple: iOS: Sign in With a Different Apple ID in the iTunes Store, App Store and iBooks Store
- Apple: iTunes Store, Mac App Store and iBooks Store: About Your Apple ID and Password
- Apple: How to Browse and Buy Content From the iTunes Store
- Apple: Use Restrictions to Prevent Purchasing on Your iPhone, iPad or iPod Touch