If you’ve ever wanted to tether your iPhone’s mobile data connection to your computer or other device without paying for your carrier’s often ridiculous fees, this tutorial could be for you.
Keep in mind that, while this should work for most carriers, yours might not be compatible with this. Also, your carrier could very well find out what you’re doing and change your data plan on their own terms.
You’ll be making a simple plist edit to your iTunes backup with a free piece of software called iBackupBot, free for both Mac OS X and Windows.
Once you make a new iPhone backup via iTunes, open up iBackupBot. Go into System Files > SystemPreferencesDomain > SystemConfiguration. You’ll then want to open preferences.plist using the integrated plist editor.
Now, you’ll need to look for an existing tethering APN with a “type-masks” of 16 or 48. Once you find that, you’ll need to replace it with the normal Internet APN, which you should also be able to find somewhere in that plist. For example, T-Mobile US’s tethering APN is pcweb.tmobile.com. That will need to be changed to fast.t-mobile.com. Note: I was actually planning on trying this myself with a prepaid $30 T-Mobile US plan, but I wasn’t able to find any APN within preferences.plist.
After you make the change, save the plist, close it, and close iBackupBot. Go into iTunes, and have it restore the backup. After a reboot, the Personal Hotspot option should be enabled.