I recently downloaded a pool game through Installer on Saturday night. After it completed the download, I noticed something along the lines of RevDip being updated. After finding out from the vendor that the game has actually been removed and added to the App Store, I removed it. The next day, as I was trying to make a phone call, I got an error on my screen saying that this device was not compatible with the iPhone 3G. I also downloaded some other apps through Installer, so I'm not sure which one it was referring to. Ever since then, when I try to make a call, the screen disappears after a few seconds, and "Call" is missing from the been button. After setting everything back to default and numerous restated and hard reboots, Apple has informed me that I need to restore my phone via my PC and iTunes. Don't worry, I did not mention anything about installing a third party app. I'm basically trying to find out how and why this happened, and to make sure it doesn't happen again.
I'm also curious if there's a difference between the Text Guru app in Cydia vs. the App Store.
Sorry for the length!

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