You can visit the iTunes Store and App Store from your iPhone, iPad, or iPod touch. If you are having issues with either the iTunes Store or the App Store, you may consider trying the below troubleshooting steps.
Note: Some features or services are not available in some iTunes Store Countries.

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2. MobileMe: Troubleshooting the Gallery app on your iPhone, iPad, or iPod touch
3. MobileMe: Troubleshooting the MobileMe iDisk app on iPhone, iPad, and iPod touch
4. Troubleshooting iPhone, iPad, and iPod touch accessories
5. Using the iTunes Store for iPhone, iPad, and iPod touch