tl; dr: Knox still bothering you after installing CF Auto Root? Install SuperSU from the Play Store to disable it!
Knox is a security tool that came in an update for the Galaxy S4 that helps protect your phone from any app doing nasty stuff to it. Unfortunately it makes life difficult for anyone who wants to root their phone to use useful apps like Greenify, Titanium Backup or any of the apps out there that need full control of the phone.
I had rooted my phone a good while ago but when I flashed Android 4.3 on it root functionality was removed. I thought CF Auto Root would fix it but it didn’t. Any time an app tried to gain root privileges a security warning would popup saying,
An application attempted to access system on your device without authorisation. This attempt has been blocked. Changing your security level to normal may solve this problem. Deleting applications obtained from unauthorised sources may improve security.
Oddly enough, Greenify worked still, and I think Adaway worked too. The oddest thing was that they worked without the usual root elevation message displaying. A later firmware update stopped those apps working as well. I think it’s SELinux that displayed that message as Knox was never actually installed.
I gave up in frustration but this evening I tried again. CF Auto Root has been updated, I flashed it and rebooted. Again the security warning showed, and there was no sign of SuperSU. Eventually I found that someone recommended installing SuperSU from the Play Store again and let it detect Knox and remove it. I tried that and, hey presto! It worked!
Now, my phone is rooted, Greenify works, and I’ve backed up a few key apps. I’m waiting on a larger capacity SD card to do a nandroid backup and then I may look at installing a KitKat ROM. I know that KitKat is rolling out but I don’t like what Google/Samsung have done with SD card access and I’m hoping ROMs won’t follow suit. Any recommendations?
OK, so I really didn’t put Kitkat on my S4 but I did put Android 4.3 on there. Most people will be able to upgrade the S4 with an OTA or KIES update but if you’ve modified your phone by rooting it then that doesn’t work without intervention.
That intervention relies on flashing a “stock rom” on the phone which is just as risky as flashing the new rom so I decided to wait until it appeared here and then grabbed the file, backed up my photos, music, settings from various apps and with some trepidation fired up Odin.
Odin is the tool used to flash Samsung Android phones and once begun, the process is painless.
So, Knox started complaining about the apps on my phone that needed root access to work. Get rid of that then! Thanks to CF Auto Root that was easy. Flash that on there with Odin and Greenify works once more and Facebook is hibernated. I sent Chainfire a donation too as I’m sure this is about the third time I’ve used his tools.
I haven’t noticed many differences, or really any except that Disk Usage works a lot faster now because of the TRIM being done on the flash memory.
Oh yeah, before I forget. I won a bar of chocolate with that KitKat. Got myself a nice Yorkie this morning. Didn’t win that time though. Ah well.
Edit: Noooooo! Knox stopped Disk Usage from scanning / which requires root. Greenify still worked which is more important but I guess Knox has some parts of the system still locked down.
Chainfire has more info on Knox and how to disable but also this bad news that disabling Knox may void any warranty on the phone. Grrr.
While the rest of the world is waiting for or installing Android 4.3 on their Samsung Galaxy S4 phones I decided to skip ahead and put KitKat on my S4. In the end it wasn’t too hard either.
Meanwhile, if you’re not able to upgrade but you’ve rooted your phone you can use the photosphere function in the Google Camera from the Nexus 5 to shoot great 360 degree panoramas. Here’s one I shot near Blarney Castle this morning.
You’ll need the camera APK from here and since it will likely force close go here and download that zip file. Copy the required libraries to /system/lib/ on your phone and photosphere will work on your stock S4!
You can try the Android 4.4 Launcher too but I haven’t. Nova Launcher works well enough for me at the moment.
Oh, and sorry
The Galaxy S4 has a very useful feature hidden in the settings. It’s called Adapt Sound and the difference in sound before and after is like night and day. I’m using the old ear phones that came with my Galaxy S2 and they’re fine for podcasts but after enabling this feature music is a lot clearer and richer. It’s quite amazing.
So, go into Settings, My device, Sound, Adapt Sound to run the sound test through your ear phones. Once that’s done and it only takes a minute or two and it will let you play a music clip with Adapt Sound on or off. The difference is quite startling.
If you have a carrier locked Galaxy S4 you can sim or network unlock it using the instructions here but only if you’re using an older modem firmware. You have to downgrade to “ME2” to unlock it as Samsung have removed those menus. You can find older firmware roms here that you can flash using Odin.
It’s scary because you could brick your phone, but use the firmware checker to find the letter code for your phone (my international i9505 is XX) and search that roms page for “me2” to get the right one.
Why the urgency? The latest update from Samsung that came out a few days ago locks things down tighter. Android 4.3 is supposedly coming in October but I have it on my Nexus 7 and the good stuff is in the Play Store apps. It might be worth disabling the automatic update checker (System Settings->More->About Device->Software update) just in case you update by accident. If only I didn’t like the Samsung camera app so much I’d put the Google Edition rom on there..
It’s crazy how many pixels the screen of the Samsung Galaxy S4 has. 1920×1080 pixels. That’s more than many computer users have on the desktop.
Of course, in 5 years time everyone’s going to be marvelling at their 4096 pixel wide screens and this will seem oh so quaint.
These are some of my most used Android apps, including Reddit is fun, Gmail, Feedly, Falcon Pro, WordPress, FBReader, Podkicker Pro, Amazon Kindle and Google Plus. Flipboard looks stunning on it and is one of the pre-installed apps that unfortunately takes up around half the 16GB internal space. The camera is superb. The background image is one I took in my back garden and processed in Pixlr Express. You can find some more photos in my Blarney post I made this morning.
It beats me why manufacturers of Android phones couldn’t make it possible to uninstall those apps I don’t need. I have all the gesture stuff turned off, and the Samsung Keyboard but they still remain on the device sucking up space. There’s still 4GB of free space so I have some breathing space still. Phew.
I really need to set up Folder Sync on this phone to copy stuff off on a daily basis.