android two-way synchronization

Good evening, I have been using syncthing for some time. I set up storage synchronization of my google pixel smartphone with my lenovo pc.

By my habit I work from both pc and phone, and it would be convenient for me to have mirroring between pc and smartphone. That is, all the changes I make on smartphone I want to find on pc, and vice versa.

As of now, from the Syncthing app on my Pixel I read that “android access allows read-only access to the selected folder.” So I can only make changes from smartphone, whereas if I make changes on pc, they are not synchronized on phone.

I would like to know if it is possible to do two-way synchronization of the Storage and set the folder type “send and receive”.

I hope I was clear in the exposition of the question, if necessary I can post more details.

Thank you, regards

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In principle, there’s no difference between Android and other OSs when it comes to how Syncthing works, which is, at least by default, two-way synchronisation. However, Android does have some limitations and restrictions when it comes to specific folder paths and their location.

The specific folder path is also the key important information missing from the original post. Please provide an example of the path that only allows read-only access. You could also try placing the folder elsewhere in order to see whether the restriction is only about the specific path or not.

I’ve discovered same problem here. I’m running Lineage OS 21 (Android 14) on my Pocophone F1.

In the past I’ve killed my micro SD card running the Syncthing shared folder on it. So I’ve used the internal memory to share data between the phone and the PC. For me the most important file is the database for KeePassXC. Starting with Android 13 the internal memory of the phone is somehow restricted. Using the default UI of Syncthing I was not able to establish a two way synchronization. For this I have to use the web UI - there it has been possible to setup a two way sync. Unfortunately this trick won’t work anymore on Android 14 and requires new privileges for the app on the Play store. I am eagerly awaiting this feature.

I also use LineageOS 21, WebUI can now add user root directories

If you are already Rooted, you can manually create a .stfolder folder in the user root directory

Or you can modify the advanced options to use an existing directory as a marked folder. FAQ — Syncthing documentation

@xiao: Thanks for this hint. I’ve double checked my synced folders - the “.stfolder” folder is always there. On the WebUI I’m able to set for each folder the “read and write” property. In the past this settings have been gone after reboot of the mobile.

Today I’ve applied a new ROM version (build date 30.04.2024) and tried again. Now the settings are permanently. So the two way sync is working now as expected. The setup is possible with the “WebUI hack”.

I’m not sure what happens, the Android Syncthing version is 1.27.3, on the PC it’s 1.27.6.

I will observe this behaviour.