I’m testing sogo4 with activesync and I’m quite impressive, I have tested some android clients. The goal is to get email, calendars, contacts with one setting, thank to activesync…hence exit imap, caldav, carddav
for now
boxer (some bugs, do not know if related to my phone)
nine (free test period)
outlook for android (odd but contact and calendar are not shared with android, only in outlook)
default email app (no more of 500 contacts, whereas I got more than 1500)
for now the winner is nine even if I should pay in two weeks
I have Bluemail on my tablet and work telephone. Quite a clean interface. And it does support exchange GAL.
For the rest I was quite unhappily surprised about the limited amount of opensource email/contacts/calendar clients.
After a lot of test I installed on my smartphone the free version of Business Calendar.
I’m use it from two years (at the begin with Zentyal and now with Nethserver) and, for my opinion, is very flexible.
Been using Business Calendar and True Phone Dialer & Contacts for a while on various Android based devices. Also, I have been synchronising these applications with Nextcloud using the DAVdriod framework.