HOLLYWOODANT215 asks in the Galaxy S3 forums,
A friend rooted my device for me. I only use the root access to see emojis. Will he need to unroot my device for me to receive [the] OTA update to jelly bean?
Another great question from the forums. The answer isn't simply a yes or a no, unfortunately. Rooting, in itself doesn't do anything. It simply allows you to do more things that you could without root. Things like changing or moving files in the system to see emojis.
Your phone is like a computer, with partitions and folders. When an OTA comes along, the first thing it does is check to see that the partitions holding the boot image and the recovery image are unmodified. It also checks the folders containing the system files to see if everything is in order. Most of the time rooting your phone simply adds a couple files without changing any others, and an OTA will flash over just fine.
The issue comes when you change any of the system files, or delete ones that should be there. In this case, the normal method to see emojis is to change the system font files. If the OTA needs to touch those font files in any way, the process will fail because they aren't the same as unmodified stock ones should be. The good news is that the OTA probably won't care about the font files and all will be well.
For you pros out there, what I'm saying is that any time you replace or remove a file inside /system, you run the risk of not being able to accept an OTA. Of course a custom recovery or kernel also means you can't accept an OTA as well.
One thing worth mentioning before we end this. You always run the risk of losing root anytime there is a system update. Hit the Play store and install OTA RootKeeper, and run it to protect your superuser access.
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