How to upgrade Xperia X (F5121) to a higher API level

Hello everybody,

I’m a Sailfish user for several years, starting with the N9. Currently I use a Xperia X (F5121). It still works fine with SFOS Adding Android support to SFOS was a great step. But now it’s getting more and more difficult to install newer apps and updates. The API level 19 (Kitkat 4.4) is too old for the most Android apps.

Question: Is there an easy way to upgrade to a newer vendor image/custom ROM/AOSP to support API levels higher than 19?
Example: Would it be possible to flash AOSP image: SW_binaries_for_Xperia_Android_8.0.5.7_r1_v10_loire.img instead of SW_binaries_for_Xperia_AOSP_M_MR1_3.10_v13_loire-1.img (configured in flashing script)?
I read a lot of stuff, but I don’t really catched the relations between Android version, Build numbers and API levels.
Do you have any suggestions? I would like to keep my phone alive.

Thanks for help


You can’t. Forget about it.

The relation is this (spelled out in several other threads); with a new-enough kernel you can use the new Android App Support, which decouples the underlying system from the Android App Support. But if your kernel is too old (Jolla C, Xperia X), you can’t, and you are stuck with the previous solution.

I think there was some coupling between what base the port had and what Android versions could be run the old way - but nowadays there really isn’t. Changing the vendor blobs “underneath” has no effect whatsoever on what can be supported “on top” of SFOS. If it was that easy everyone would be doing it since day one.


There is not an easy way and there is not an hard way to do that.

The recommendation then is to remove android support and live with pure SFOS.

Thanks for your replies and straight answers.
I was afraid that this would be the answer and that this was discussed already.
I would remove Android support immediately, but there are so many diseases like authentication apps for banking and VPN connections and finally whatsapp (there is no sports club or scool class without chat group).
It’s hard to accept, that hardware is couple so strong with OS. It makes no sense and is obviously driven by obsolescence.

Thanks again, bye…

It’s only that the kernel is too old.