LineageOS on a Samsung Galaxy S9

Over the years, I’ve used LineageOS and its predecessor CyanogenMod on my personal devices such as the Samsung Galaxy S4 and, for the past few years, on the Samsung S5. But my S5 is aging so I was looking for a replacement. There is a LineageOS port for the Galaxy S6 but it seems to be quite experimental, I kept having power drain issues due to some system task starting to run wild after a few days. There’s also a version for the Galaxy S7 which is already kind of hard to get on the market but a version for the S8 is missing. The more surprised I was to see that there is a version for the relatively recent Galaxy S9.

This might have something to do that the Galaxy S9 is one of the first devices that is compliant with Google’s Project Treble, which makes a clearer separation between Android and the drivers required for individual hardware. Sounds good to me! I would have preferred to run LineageOS on a somewhat less expensive device such as the Galaxy J line but there are no LineageOS builds for those at the time of writing.

Let’s Install

Installing LineageOS on the S9 was actually quite straight forward. The first thing to do is to unlock the bootloader which can be done in the ‘developer’ menu that can be made visible by tapping on the “build number” field in the system menu several times. In the ‘developer’ menu, activate ‘OEM unlock’. I didn’t do this at first so flashing the recovery image (see below) failed. There are rumors the bootloader can only be unlocked after a week of using the phone but this was certainly not the case for my device.

Next, I downloaded the TWRP recovery image the LineageOS page for the S9 points to, the LineageOS image itself and the root access apk zip file. I didn’t download any GApps image as I noticed in the past that none of the apps I am using requires the Google APIs, plain Android is enough! Very liberating!

The First Reboot Fails

After installing the TWRP recovery image, I booted into recovery and installed the LineageOS binary and root apk zip file from an SD card. Easy, or so I thought. At the end of the flash process a few error messages were shown that there was something wrong with the data partition. Not much to be done I thought and rebooted. The LineageOS logo came up but the boot process ended with a failure message about the data partition not being accessible. O.k., so back to the recovery image for some tweaking. After a while I figured out that the problem was due to the data partition being encrypted and that formatting instead of deleting it was the solution. This option is a bit hidden in the TWRP installation menu so it wasn’t the obvious first choice. After re-installing with the formatting option activated, the device booted like it should.

New Safeguards Installing APKs

The first thing I did once the system was running was to check how to install the F-Droid store on Android 8. Rumors had it that Google has changed again the way software can be installed outside the Play store to make it safer for the ordinary user. On LineageOS, the additional safeguard was to move the F-Droid APK file from the download folder into the documents folder with the file explorer app and then execute it from there.

Almost Working Now

After installing a number of applications I remembered that I read that some people had issues with the camera when installing LineageOS over an older original Samsung software. And indeed I had the same problem, the camera would not work. Fortunately, I could get the Samsung software that people in the forum reported is required to get the camera working so I flashed the S9 back to its original software. Once done, I tested the camera which was working with the original Samsung software and then flashed back to LineageOS once more. That cost a bit of time but was well worth it because the camera started working.

Improvements over the S5

And that was pretty much it as far as the installation process is concerned. I’ve been running LineageOS on the S9 for a few days now and haven’t seen any major hickups so far. Things that have much improved over the S5 are the much better camera and the much faster processor that makes heavy apps like Firefox and OpenStreetmaps for Android (OSMAND) run much faster than on the S5. Also, I am really happy to have the clock and status indicator back on the display when the device is locked. The last time I had this feature was on my Nokia N8 many years ago and I could never understand why this very useful feature was not copied by other companies. One thing not immediately visible is the vast number of LTE frequency bands supported by the S9. Compared to the S5, which mainly supported European and Asian bands, the S9 comes with a much broader range of supported bands, which is especially important if you happen to be in North America every now and then. The S5 does work there as well but some important bands were missing so I would sometimes have no reception.

And one more thing I find that has much improved is the Wideband-AMR sound quality when making phone calls. It’s like night and day compared to the S5, which could also do WB-AMR. Also, the speaker in the device has improved, so making phone calls in handsfree mode or listening to music while the phone is on the desk is much better compared to the S5. The only thing that so far really bugs me about the S9, except for the high price, is that the battery can’t be replaced. I would sacrifice quite a bit for a replaceable battery but I don’t see a good alternative that works with LineageOS at this point in time.

So lets see how the S9 fares over time, watch out for a follow up post!