Is this possible?
Has anybody done this?
Which third-party apps would you recommend?
At the moment I'm using Simple Calendar, but don't mind which so long as it works.
Thanks for your interest in GeneralSync!
Is this possible?
Yes, GeneralSync does not depend on specific Google applications or services.
Has anybody done this?
Yes, most testing is done on isolated devices without Google applications.
Which third-party apps would you recommend?
You should be able to use any calendar and contacts app that supports reading from and writing to the Android calendar / contacts interfaces. These interfaces are part of the operating system and do not depend on anything Google.
I assume privacy is an important factor for you and your device does not yet have a privacy-friendly calendar app; in that case, you might be interested in the calendar app Etar, which provides solid calendar features without tracking you. Most devices do come with a non-google contacts app; but if you want to switch to something different Simple Contacts might be what you're after.
At the moment I'm using Simple Calendar, but don't mind which so long as it works.
Simple Calendar does work with Android calendars and thus supports GeneralSync, but you need to manually add the calendars you want to see using the option "CalDAV Synchronization" (the CalDAV protocol has nothing to do with that feature though, no idea why that name was chosen). It seems as if the app is primarily designed for local calendars without synchronization, though – calendars provided through Android don't seem to be accessed directly, which may cause additional delays and duplicated events or prevent correct conflict detection in rare cases.
Thank you for this information. I have now managed to sync GeneralSyncCalendar to Etar. I have installed Simple Contacts but cannot find any way of using GeneralSync to sync it with my TB contacts. If anybody could point me in the direction of any instructions, I would be very grateful.
I have installed Simple Contacts but cannot find any way of using GeneralSync to sync it with my TB contacts.
Simple Contacts directly operates on system-wide Android contacts, so you shouldn't need to do anything specific to use GeneralSync with Simple Contacts.
The basic approach is thus the same as with calendars: Import your existing contacts, for example by selecting them in Thunderbird's address book window and dragging them into a GeneralSync address book while holding the Ctrl key. They will then appear on the Smartphone.
If you see the contacts within the GeneralSync address book on PC, but they don't appear in Simple Contacts although changes from calendars are synced properly, there are multiple potential causes:
You changed Simple Contact's settings to only display contacts within a specific 'account' or 'group'. Make sure that no filters are active within the app. If I recall correctly, the option to select which contacts shall be displayed is accessible through the 3-dot-menu in the top-right corner of Simple Contact's main screen.
You did not permit Simple Contacts to access your contacts.
You did not permit GeneralSync to access you contacts during the first run setup. You can check that by opening the GeneralSync app and tapping on the address book: a warning is displayed between the title and the list of devices if the permission is missing.
You disabled automatic synchronization in Android's settings. You can check that by looking at the main screen of the GeneralSync app: if any form of synchronization is disabled, a red/pink bar with a warning message is displayed at the top of the screen.
You use some form of isolation between Simple Contacts and GeneralSync. For example, there are security features that may permit you to differentiate between "work" and "home" apps, and apps in each group cannot access contacts of apps in the other group. Another example would be third-party apps and functions within some versions of Android to limit an app's access to the contacts list for privacy reasons.
This list is not necessarily conclusive.
Solved! Thanks a million for all of your help. It is much appreciated!
So sorry. It's me again. I synced my Thunderbird contacts list successfully once, but it is not updating with new content (in either direction). What could I be doing wrong?
I synced my Thunderbird contacts list successfully once, but it is not updating with new content (in either direction).
The two most common issues would be that you do not have a proper network connection (double-check both devices are connected to the same network and that the 'last synced' timestamp in GeneralSync increases properly) or that you view the wrong address book on Android (if you accidentally hide the GeneralSync address book and continue to use an old address book you imported from, you don't see GeneralSync's changes and your changes end up at the wrong place).
To rule out weird issues with low-level device drivers and similar issues, you should also try restarting both the PC and the smartphone. I haven't experienced such issues with recent devices, but it can never hurt to try. 
Did that help? If not, can you check if the GeneralSync App and the GeneralSync control panel on the PC display a recent 'last synced' timestamp and mark the sync relation for the address book as 'active'?
