There are plenty of reasons to unroot android phone due to some issues like:
No Warranty: If you don’t know that read it carefully. Yea, rooting your android phone kills its warranty. It does not matter whether your phone is one day old or it is a 2 year old android mobile. So, if you are getting some issues in hardware of your smartphone which is covered in warranty. Then, you must unroot your android mobile before going to Service Centre.
Lack of Security: Yes! You heard it right. There is lack of security in your rooted android phone as the apps to which you have provided root permissions can read or modify anything including your contacts, mails, files, call logs etc. So, if you are uncomfortable with this then you must consider to unroot your android phone. You can check out best antivirus for android to increase security of your android mobile.
Default OS becomes stable: Rooting your android phone sometimes makes it unstable. You may encounter some randoms reboots, random crashes of applications and systems. So, If you are facing such issues then its time to flash stock ROM and unroot it completely.
Method 1 – Unroot your Android phone using SuperSU app
Below, We are sharing best method to unroot android phone easily by one click.
1. First of all, Download and Install SuperSU app from Google Play Store.You can also install it straight from google search check it out here http://www.getontopc.com/2016/01/how-to-install-apps-straight-from.html?m=1
2. Go to Settings in SuperSU app.
3. Click on Full Unroot and You are done.
4. Restart your android mobile and Uninstall SuperSU app.
Your phone is unrooted successfully now.
Method 2 – Unroot your android phone using Root Explorer
This method is manual method of removing root files(su, busybox etc.). Try this method only, if above method does not work for you.
First of install Root Explorer in your mobile from Play Store.
1. Open Root Explorer and Grant root permissions to Root Explorer.
2. Now, follow this path – system -> bin.
3. Now, Find two files – su and busybox, Simply delete both of them.
4. Now, Click back button and find app folder.
5. Just, Delete Superuser.app from there.
6. Now, Restart your android phone and your phone must be unrooted now
source:http://www.getontopc.com/2016/08/how-to-unroot-your-android-device.html?m=1
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Nice tutorial...