Foreword:
As I have now been repeatedly asked about the above topic, and it has already been mentioned here in the forum, I would like to document something on this matter at this point.
I have deliberately called the topic Not! synchronising the logbook, since synchronising in principle is something different. (For that I would work with tools like diff, rsync & co. and automation.)
Initial situation:
I use 2 devices (max. 3) on which VFRnav is installed.
- Tablet (my personal main device = Master)
- Phone (running, for example, as a backup; I also use it for spontaneous photos)
- Device ??? … the following explanation applies here as well
Example:
On my flights three weeks ago, I always flew with both the tablet and the phone.
Two weeks ago, I only flew with the tablet. I did not have the phone with me.
This week I forgot the tablet and flew only with the phone.
What I want:
I want to have the same data status of the logbook on all my devices.
How can this be done?
1. Option
For the first two cases above, only the tablet has all flights in the database.
In the third case the tablet is missing and the phone has a “data gap” from case 2.
→ …so what should now be synchronised with what? = not possible!
→ To save work I could say: I take the tablet as the master and sync it with the phone. Afterwards I manually enter the missing flights on tablet and phone …with a few flights you’d just do it manually of course.
2. Option
Each flight is uploaded to a storage medium accessible to all devices.
That flight is then “unsynced” to all devices.
…every flight? to all devices? …
In case 1 that would be 2 identical flights from tablet and phone! …and so on.
→ so that is out of the question!
…and: what if a flight was stored incorrectly or incompletely?
From my experience:
As already mentioned above, I also use the phone for taking photos etc. In doing so, the running VFRnav is pushed into the background. It has happened many times that either the recorded flight then had gaps, or VFRnav began the flight recording all over again. Attention! …this is not due to VFRnav, but among other things to Android’s task handling. → ….if this flight were automatically synchronised …..that would be a big mess!
My opinion as a currently good practicable solution:
Designate one device as the master, which you always fly with. All other devices can then easily be synchronised with this master at any time …and you can quickly type in any missing flight by hand.
Here is the procedure for logbook synchronisation with multiple devices:
Start menu -> My Flights -> three dots
Export logbook
Choose the file format (I prefer Excel because of post-processing on PC)
Important note: the association of the stored tracks is lost in the process!!!
This is a major disadvantage of this variant. If you don’t want that, choose the KML format.
Select a storage location
– Attention! here choose a folder with personal rights, e.g. Documents
Now the logbook is saved in the above folder. Great, you have a local backup right away.
But how do you get it to another device???
I think the simplest method and classic is to email this file to yourself.
The file must be transferred to a storage location where all devices can access it.
This can be a home server, a cloud storage on the internet (Google, Apple & co.)
Of course a USB stick works too—here you may need an appropriate adapter.
The file now has to be downloaded and saved on the target device, e.g. phone.
Let’s assume the email route:
we download the file from the email onto our phone. Typically the file then resides in the Download folder. I recommend copying it immediately into the personal folder to avoid access-right issues later. The copying is easiest with a file or directory explorer of your choice, or the preinstalled tool. (I use X-plore full version by Michal Bacik, for example.)
Import logbook into VFRnav:
Attention! …before we start overwriting/importing the logbook on the phone, we must first export the existing logbook on the phone!
The same procedure applies as described above. We check whether the logbook file is indeed in the folder and has a reasonable file size, e.g. 77 KB or so. …the file should not be 0 KB! …only if everything is OK here can we proceed!
Now we delete the existing logbook on the phone:
Settings → Logbook → Delete logbook
Then we import the new logbook
The same procedure applies as for the export described above, only we choose Import instead of Export!
We navigate to the folder (Documents) where we placed the file and select it.
Now we should have the same logbook on the phone as on the tablet.
If anything didn’t work, we can always import the old phone logbook from the folder.
We can do the same synchronisation with a third device.
I hope the explanation was understandable. 
I believe this is the most practicable method so far for distributing the logbook.
Maybe there are better ideas or solutions? …I’d be grateful for those too!
Pilot greetings, simply fly
Karsten
Cool. Please