[LG G5 Questions & Answers] JakesBake:
Hey all,

I made this account to ask these questions. I'm not familiar with these forums or Android in general, so please go easy!

First of all, I'll give a bit of background to my concerns, in case I don't end up asking the right questions. Please excuse my ignorance of certain terminology, and general lack of knowledge. If you want to skip to the questions, feel free, but I would appreciate if you read the backstory so that you might be able to give advice or information with more context. If anyone takes the time to lend a hand, I would be very grateful. If this type of question is better suited somewhere else, please let me know. Thanks!

I have recently become a bit paranoid about the security of my device - an LG G5 H831. The main reason for this being that I realized that my locker at work could have been open for 2-3 hours at a time, multiple times a day, for a couple months (Yeah... Whoops...). Now if that doesn't annoy you enough to leave this thread, please go on! I have no reason to believe that somebody has tried to snoop or mess with my phone while it was in there, and I wouldn't expect it from my coworkers. I also use a swipe pattern on my phone for protection (along with a fingerprint, but it only needs one or the other). Nonetheless, I am a paranoid person and I have some concern about the possibility that maybe (x1000) there could be a really determined person who, over time, would make their way into my device while it was unattended. I haven't noticed anything strange on my device or accounts, but I am worried about the possibility of someone putting some sort of malicious stuff on my device, or tinkering with the settings in a way that could jeopardize my phone/ personal information. I am most worried about information being leaked or my phone being actively monitored. I don't know much about what is possible in those regards. Regardless of the low likelihood, I would like to make an effort to secure things, to the best of my ability, for the sake of peace of mind.

Now, onto the questions:

1) I have read a lot about the LG G5 H831 model not being able to be rooted. Is this true? I don't fully understand rooting at all - I have only read about it over the past couple days and have a very basic knowledge of what it means.

2) If it is possible for it to be rooted, how possible is it that it could be performed in a situation as described above? If it is possible that my phone is rooted, how can I check to be certain? I am concerned that someone could have rooted my device and installed something malicious or changed settings for malicious purposes with this level of access.

3) Also, to go even further into paranoia land, how possible is it that someone could root the phone, do some malicious tinkering of any sort, then UNROOT it, making evidence of the root undetectable, while the malicious app or whatever else is still intact?

4) Is there anything other than rooting that could be cause for concern? Anything else dangerous or insecure that could compromise the device, and evade my phone's security systems? Any basic settings that might be messed with that could compromise my security, such as call/ text forwarding or anything along those lines? I keep Unknown Sources unchecked, but I suppose it isn't difficult for a would-be snoop to check/ uncheck it.

I apologize again for poor terminology, and perhaps the questions aren't sensible for reasons that I am unaware of (beyond low likelihood, of course). Any advice on these concerns is greatly appreciated.

5) Now, if the phone CANNOT be rooted, does that mean that there is nothing else that could have been done that could go undetected by my phone's regular defense system? Anything that could possibly hide from App folders, or system settings that could be adjusted, or anything along these lines?

6) I guess the quick answer that I need in this regard would be: Is there ANYTHING that can be done to this phone with malicious intent that could survive a factory reset? I plan to do a reset to be sure, but I want to be certain that this is definitely going to get rid of any potentially dangerous stuff going on in my phone. Are there non-root dangerous apps or settings that might survive a reset?

7) If the phone could have been rooted, system settings messed with, or compromised in any way, what steps would you advise to securing my device, with the most certainty reasonably possible?

I sincerely appreciate anyone who takes the time to answer any or all of these questions. I feel kind of silly even writing this out, as I know the low likelihood of something having happened at all, let alone the depth of theorizing I've engaged in. However, the thought of personal information being compromised, being spied on, or my phone having anything malicious going on in it is something I want to deal with with the utmost thoroughness and certainty.

Have a good one!