What is the difference between temp root & pemanent root? What is a soft reboot? The AT&amp;T Samsung Galaxy Note 4 currently has temp root, but no permanent root.  I am not 100% sure I understand the difference.

From what I gather, temp root is lost if the phone is rebooted in a typical fashion:


Battery drains to the point the phone shuts off
Pull the battery, let the electricity discharge, put the battery back in, and boot the phone normally
Tell the phone to reboot (for example by holding the power button and using that menu)


However, I remember reading (sorry lost the links) that a "soft" reboot will not force you to lose root.  I'm not clear on what a soft reboot is.  The description I read said something about the software rebooting but not the kernal.  Finding information on this is troublesome since the terms "reboot" and "reset" have become intermingled by nontechnical users.

For example, Technopedia describes one thing, while another site talks about hard vs soft reset.  Both were results for the search term what is a soft reboot.

There's a link on XDA Developers where a user is asking the difference between a soft reset and a reboot: http ://forum.xda-developers.com/showthread.php?t=620337

Over on Android Central, there's a thread where the people who reply get their vocabulary mixed up: http ://forums.androidcentral.com/htc-evo-4g/15765-soft-reboot.html

What are the differences between a permanent root from a user functionality perspective?  What kinds of apps do not work, or don't work well, with temp root?

What is a soft reboot?  What are the benefits?
Permanent root vs. Temp root:

Permanent root:


Root persists a reboot
No need to re-root after rebooting
Root access in boot phase (needed for some apps that run after Android is booted)
Usually prevents any future OS updates
Usually voids warranty


Temp root:


Root access is lost after a reboot of the device
Needs to re-root after a reboot
No permanent changes to the OS
Allows future OS updates1
No root access right after booting


1: Only if the device has no active "root check" (like some Samsung devices)

"Soft" reboot vs. normal reboot:

Normal reboot:


Complete and safe shutdown of the device
Proper halting of the CPU
Restarts through the bootloader with possible access to the recovery and download mode


"Soft" reboot:


Reboot of the Android framework
No restart through the bootloader
No access to recovery and bootloader
The system is abruptly halted/killed (ie. unsafe)
Most of the hardware is still running (ie. no need to re-enter your SIM-Pin, WiFi does not need to re-authenticate)
Can be achieved by killing he system_server process
Requires root access/Custom ROM
(Preserves temp root)1


1: Only if the device does not check for modifications after the initial boot (like some Samsung devices)