Why are half my apps unusable on my LG G3?

[Android Central Question]

I use the google now launcher on my LG G3, but every time I restart or power off then turn on my phone, it says I have to use the LG default launchers.

When I choose one, half my apps are unusable, sometimes even system ones, and have the android symbol. When I click on it, it says, "app is not installed".

I would do a factory reset, but currently, my keyboard and settings are unusable. Please help.

 

[belodion]

There's something badly wrong there, and I can't offhand think of any likely reason, unless perhaps it's failing software.
Try booting into Safe Mode to see whether that helps in any way. It may at least restore your keyboard and access to Settings.
Tell us how it goes.

 

[CharlieMKy6]

There's something badly wrong there, and I can't offhand think of any likely reason, unless perhaps it's failing software.
Try booting into Safe Mode to see whether that helps in any way. It may at least restore your keyboard and access to Settings.
Tell us how it goes.

It did not work. Still half of my apps, including keyboard and settings, are still unusable.

 

[Mooncatt]

There's something badly wrong there, and I can't offhand think of any likely reason, unless perhaps it's failing software.

Or perhaps failing hardware, causing the software to fail? That phone is rather old, so it wouldn't surprise me. I'm also wondering if maybe there's some compatibility problems as well.
@CharlieMKy6 welcome to the forums. I'm about as stumped as Belodion. It's rare that I jump right to factory resetting your phone, but I think this is one of those exceptions. It sounds like there's too much going to try digging through. I know you were worried about the keyboard not working, but that will revert to stock just like everything else and you shouldn't have to worry about it. I don't remember if Factory Reset Protection was enabled on the G3, but I would make sure you know your Google login info before you reset, just in case it asks.

Before you do it, I would try getting anything you can backed up (but hopefully you've already been doing that), and maybe even try to connect it to a pc to try accessing media and such.

 

[CharlieMKy6]

Or perhaps failing hardware, causing the software to fail? That phone is rather old, so it wouldn't surprise me. I'm also wondering if maybe there's some compatibility problems as well.
@CharlieMKy6 welcome to the forums. I'm about as stumped as Belodion. It's rare that I jump right to factory resetting your phone, but I think this is one of those exceptions. It sounds like there's too much going to try digging through. I know you were worried about the keyboard not working, but that will revert to stock just like everything else and you shouldn't have to worry about it. I don't remember if Factory Reset Protection was enabled on the G3, but I would make sure you know your Google login info before you reset, just in case it asks.

Before you do it, I would try getting anything you can backed up (but hopefully you've already been doing that), and maybe even try to connect it to a pc to try accessing media and such.

As I've said before, settings is one of the apps that is unusable, I've tried doing a factory reset, but

 

[Mooncatt]

As I've said before, settings is one of the apps that is unusable, I've tried doing a factory reset, but

My mistake, I should've clarified that I meant to factory reset via the hardware keys so you don't have to access the keyboard or settings app. This video explains it well enough.

https://youtu.be/ZPlQeNviftk

 

[VidJunky]

Initially it sounds like you are using two different accounts (Gmail addresses)…. In the past, I can't say currently as things change and I haven't been in this situation in some time but, in the past if you logged into the device as, say whmcgee@gmail.... downloaded some apps and then switched to mcgeeunit@gmail.... The apps downloaded under the one email would no longer work while logged in to the other account, and of course vice versa. It may be kind of late as you are about to factory reset your device, but when you are using the Google Launcher is it as the same user you logged into the phone with?

 

[B. Diddy]

Welcome to Android Central! Can you clarify -- are you using the stock LG launcher, or a 3rd party one?

Also, did you use the "Move to SD" option for any of those apps that aren't working?