We’re now in direct contact with Google in this case and hope that we’ll receive more information soon, so that we can provide a solution. 
According to Google,
DIRTY after each call/SMS will be fixed with Android 8.0,There are possible workarounds and solutions. We’re having a look at that.
Could DAVdroid introduce a workaround for this case? Somewhere in DAVDroid, there must be a place where local and remote contacts get compared. In that place, one could possibly check for these three things:
REVthen, we just discard this?
I have no Idea if this opens up a huge can of worms, but If (as you suggest) this will remain in all of android 7, then we’re stuck with this behaviour for the next few years. With the vast majority of people getting to 7 this or next year. And then dragging this bug around for 3-4 years to come until android 8 is widely available.
Should be worked around by davdroid/faaaa330 (further testing required).
Can I help testing somehow? (I only have my regular day-to-day phone for testing, but I do have backups, just in case).
@ccoenen said in Android 7+: Contact sync after each call and SMS:
Can I help testing somehow? (I only have my regular day-to-day phone for testing, but I do have backups, just in case).
We could always use some testing. Are you interested in beta testing? Where did you get DAVdroid from/which signature?
@rfc2822 said in Android 7+: Contact sync after each call and SMS:
@ccoenen said in Android 7+: Contact sync after each call and SMS:
Can I help testing somehow? (I only have my regular day-to-day phone for testing, but I do have backups, just in case).
We could always use some testing. Are you interested in beta testing? Where did you get DAVdroid from/which signature?
I’m normally using the release from F-Droid.
Hello,
I’ve sent you a updated version of DAVdroid to your email address. Can you please try if it works?
Important: you need to completely uninstall and re-install DAVdroid, otherwise the signatures will not match!
Should be worked around with DAVdroid 1.4.0, please test it and tell us whether it works for you.
@devvv4ever I received that mail, however I couldn’t simply install it over the current F-Droid version, I didn’t have the time to double check my backup for the uninstall-reinstall-restore cycle then. Sorry for letting you wait.
From what I can tell (very short testing period so far), It will be dirty once after the update, as two things change: the REV and the PRODID. I haven’t seen single REV changes since the update to 1.4. I also didn’t notice any sync problem. I’ll report back if anything comes up. Looks good to me.
So far, everything looked alright. Tonight I had one incident that I can’t quite put my finger on it: One of my contacts just lost their groups. Here’s the diff (anonymized):
diff --git a/55cd82aa-5d0d-444e-b414-3905d2193d42.vcf b/55cd82aa-5d0d-444e-b414-3905d2193d42.vcf
index 3ae5862..1a0367f 100644
--- a/55cd82aa-5d0d-444e-b414-3905d2193d42.vcf
+++ b/55cd82aa-5d0d-444e-b414-3905d2193d42.vcf
@@ -1,13 +1,13 @@
BEGIN:VCARD
-VERSION:3.0
-PRODID:-//Sabre//Sabre VObject 4.1.1//EN
+VERSION:4.0
+PRODID:+//IDN bitfire.at//DAVdroid/1.4.0.2-ose vcard4android ez-vcard/0.10.
+ 1
UID:55cd82aa-5d0d-444e-b414-3905d2193d42
-CATEGORIES:work,friends
FN:First Name Last Name
N:Last Name;First Name;;;
TEL;TYPE=cell:+49 123 4567
EMAIL;TYPE=work:something@example.com
ORG:some org
BDAY:18000415
-REV:20170212T223553Z
-END:VCARD
\ No newline at end of file
+REV:20170215T095941Z
+END:VCARD
So, instead of the categories, suddenly there’s a line just saying <space>1 (1 with leading space). This is not forum formatting, or the leading space of the diff format, this is actually in the vcard.
I did have other syncs that same day which still have their catetegories. They also have the <space>1 extra line.
Again, not sure if this is related, but I thought I’d mention it.
I now believe this to be unrelated, I started another thread for the CATEGORIES issue.