Apple has made it easy to block sites in the release of iOS 7. Websites that are blocked via the Restrictions menu will be blocked in every browser. You can block one site or block all sites but allow approved sites.
Step
Method 1 of 2: Blocking Certain Sites
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Step 1. Open the Settings app and tap on “General“
The general iPad settings will appear.
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Step 2. Tap “Restrictions” to open the parental control menu
If Restrictions was previously enabled, you will need to enter your Restrictions passcode to continue.
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Step 3. Tap "Enable Restrictions", then create a passcode
This passcode must be different from the one you normally use to lock iPad. Make sure this code is memorable because you will need this code to make changes.
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Step 4. Tap on “Websites” in the “Allowed Content” section
Site restriction controls will open.
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Step 5. Tap "Limit Adult Content" to block certain websites
This option is to add sites to block, as well as block websites that contain adult content.
If you want to block all sites except for a few, see the next section
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Step 6. Tap on “Add a Website” in the “Never Allow” section
This option is for entering the addresses of the websites that you want to always block.
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Step 7. Type in the address of the site you want to block
The site you want to block will be added to the " Never Allow " list and prevent it from loading in Safari or any other web browser on the iPad.
Add all versions of the site. For example, blocking "wikihow.com" doesn't necessarily block the mobile version. You should also add "m.wikihow.com"
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Step 8. Continue adding the sites you want to block
Add sites whose access will be restricted. If you find that there are a lot of sites that you want to restrict, it will be easier for you to block all sites and only allow certain sites. For more details, see in the next section.
Method 2 of 2: Allowing Only Certain Sites
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Step 1. Open the Settings app then tap on “General“
Sometimes it's easier to block all sites and then only allow certain sites, such as allowing certain websites for your child.
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Step 2. Tap "Restrictions" then enter your passcode if prompted
A passcode request will only appear if you have enabled restrictions previously.
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Step 3. Tap on “Enable Restrictions“
You will be asked to generate an access code that is specific to Restrictions. This code must be entered each time you want to make changes.
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Step 4. Tap on “Websites” in the “Allowed Content” section
This option is for customizing the settings of the sites you block.
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Step 5. Tap on “Specific Websites Only“
Access to all sites will be blocked except those you have allowed.
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Step 6. Tap on “Add a Website” and enter the sites that you will allow
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Step 7. Continue adding websites
You can add any site to this list at will. Any sites you add can be accessed from Safari or any other browser you have installed. All other sites will be blocked.