To sync with Android I use DAVX5 which runs a background sync service (open source and non-root). I had a lot of issues getting it working, could be because of different CalDAV implementations. DAVX5 to ZOHO calendar sync takes forever.
Evolution on Ubuntu has pretty good CalDAV support, but it would refresh the entire calendar each time upon switchin between the mail view and calendar view. Refreshing that ZOHO calendar takes forever and ZOHO has pretty frugal rate limits, so it ends up soft-banning me.
Latest Thunderbird has a CaldDAV incompatibility where it expects a different HTTP success code. ZOHO gives a 200, but Thunderbird expects something else. (PS Thunderbird CalDAV code is written in JS). PS This only happens on the second calendar. Whenever you add a second one, it starts failing.
I also use zoho (for mail, calendar, contacts) for my family and I...and yeah the first time i set it up with DavX5, it was odd to say the least...though not sure if it was zoho's fault, or maybe both some possible glitch with zoho and DavX5, that didn't quite jive with my brain - at first. Now, i see no issues with Davx5 and zoho cal and contacts...at least it sync really well on my android phone. I have not tried Evolution for years (and certainly not with zoho yet), since i tend to default to thunderbird...But am about to set up my partner on one of the Gnome-based linux distros once their Windows 10 dies later this year...and considering how they like to use their computer and their workflow, gnome seems most appropriate for them, so have been considering suggesting for them to us Evolution as email client...so will be interesting to see how zoho works there. (Glad to hear it works for you!) As i noted, i like to use thunderbird, and as far as mail and calendar, actually i guess i have been lucky, since zoho seems to be working great for me - and for a couple of years now! However, contacts synching has never worked right - like, never at all. Sure i can export contacts from zoho and import them into thunderbird...so the issue is not the basics of contacts functionality within thunderbird per se...but the syncing between t'bird and zoho is certainly an issue, and have not had a chance to dive deeply enough to see if the issue is a t'bird issue or zoho...although like calendaring on my android phone, contact synching is not an issue with zoho from my phone (again via Davx5)...so, i'm confused. But, agreed with your points: i'm happ[y zoho customer, but they're not perfect...then again, at their low costs, i kinda can't complain too much. ;-)
To sync with Android I use DAVX5 which runs a background sync service (open source and non-root). I had a lot of issues getting it working, could be because of different CalDAV implementations. DAVX5 to ZOHO calendar sync takes forever.
Evolution on Ubuntu has pretty good CalDAV support, but it would refresh the entire calendar each time upon switchin between the mail view and calendar view. Refreshing that ZOHO calendar takes forever and ZOHO has pretty frugal rate limits, so it ends up soft-banning me.
Latest Thunderbird has a CaldDAV incompatibility where it expects a different HTTP success code. ZOHO gives a 200, but Thunderbird expects something else. (PS Thunderbird CalDAV code is written in JS). PS This only happens on the second calendar. Whenever you add a second one, it starts failing.
So it is quite a pain, at least with ZOHO.