Version 1.4.0.1:

Android 7 workaround bugfix (only applies to Android 7)

* use local version of contact before calculating hash code
* don't stop upload sync if there are deleted contacts

Version 1.4.0.1:

Android 7 workaround bugfix (only applies to Android 7)

* use local version of contact before calculating hash code
* don't stop upload sync if there are deleted contacts

Version 1.4.0

* Android 7 behavior of marking contacts DIRTY on every SMS/call (although no relevant contact data are changed¹) is workarounded by using hash codes. Now, contacts won't be uploaded after every call/SMS anymore.
* Fixed display problem of sync intervals in DAVdroid account settings: previously, the Android calls were synchronous. Note that Android 7 will rewrite sync intervals of < 15 min to 15 min automatically. This is an Android "feature" and can't be changed by DAVdroid.
* Upgrade to okhttp 3.6.0, which provides some HTTP/2 and other improvements.
* More verbose logging.

Version 1.4.0

* Android 7 behavior of marking contacts DIRTY on every SMS/call (although no relevant contact data are changed¹) is workarounded by using hash codes. Now, contacts won't be uploaded after every call/SMS anymore.
* Fixed display problem of sync intervals in DAVdroid account settings: previously, the Android calls were synchronous. Note that Android 7 will rewrite sync intervals of < 15 min to 15 min automatically. This is an Android "feature" and can't be changed by DAVdroid.
* Upgrade to okhttp 3.6.0, which provides some HTTP/2 and other improvements.
* More verbose logging.

Version 1.3.8

* added verbose information about current local and remote resource to debug info (helps to find faulty contacts/events, for instance when they're not parseable)
* new translations, which also fix a crash in the Spanish version

Version 1.3.8

* added verbose information about current local and remote resource to debug info (helps to find faulty contacts/events, for instance when they're not parseable)
* new translations, which also fix a crash in the Spanish version

Version 1.3.7.1

Hotfix: workaround for "contacts/calendar sync not available" on buggy firmware

Version 1.3.7.1

Hotfix: workaround for "contacts/calendar sync not available" on buggy firmware

Version 1.3.7

* delete local contacts at sync when no CardDAV collection is selected
* change authentication restriction to domain instead of host name
  (fixes missing authentication when downloading iCloud images)

Version 1.3.7

* delete local contacts at sync when no CardDAV collection is selected
* change authentication restriction to domain instead of host name
  (fixes missing authentication when downloading iCloud images)

Version 1.3.6

Core:
* better detection of whether OpenTasks is installed or not (fixes Android 7 phantom sync entries)
* automatically enable/disable task sync when OpenTasks is (un)installed
* fix "permissions required" notification
* update to SDK level 25 (Android 7.1.1)

CalDAV:
* remove ORGANIZER from all VEVENT components if there are not attendees

CardDAV:
* update to ez-vcard/0.10.1
* improve parsing of uncommon REV/timestamp formats (fixes current Nextcloud/OwnCloud Contacts problems)
* ignore invalid PREF values

Version 1.3.5

* bug fix: contacts always downloaded from beginning until there's a successful sync
* ical4android: use the same ORGANIZER for all VEVENT components
* minor improvements and bug fixes
* gradle/okhttp upgrade

Version 1.3.4.1:

* allow renaming of accounts (as far as possible)
* various bug fixes

Version 1.3.4

davdroid:
* add app-wide HTTP proxy setting
* debug info: send inline on Android <4.1 and when creating an attachment doesn't work

ical4android:
* upgrade to ical4j 2.0 final
* ignore DTSTART instead of DUE, if DTSTART>DUE
* better handling of events without DTEND/DURATION
* handle TransactionTooLargeException correctly when a single operation is too large

vcard4android:
* handle TransactionTooLargeException correctly when a single operation is too large
* rescale photos when they're bigger than ContactsContract.DisplayPhoto.DISPLAY_MAX_DIM
  before inserting them into the Android contact provider

Version 1.3.3.1

Core:
* share debug info: always use attachment (before: send inline if it was small enough)
* use FileProvider for debug info attachment (for Android 7 compatibility)
* new translations

dav4android:
* rewrite authentication scheme parameters to lower case (to accept "Realm" as well as "realm")
* disable compression for GET requests because it may change the ETag

vcard4android:
* better handling for empty FN/N (for instance, organization-only contacts without structured name)

ical4android:
* upgrade to ical4j 2.0.0-rc2

Version 1.3.3

* authentication: always use UTF-8 instead of ISO-8859-1 for Basic credentials to implements RFC 7617
* contact sync: remove "disable RFC 6868" option (RFC 6868 is now always enabled)
* event sync: don't set event classification (CLASS:PRIVATE) when "privacy" is "default"
* task sync: ignore invalid DUE values which are before DTSTART
* minor bug fixes and improvements (including internal refactoring)

Version 1.3.2.2

* work around HTTP/2 problems with OPTIONS
* fix connection leaks

Version 1.3.2.1

* hotfix for event synchronization on Android <4.2
* various Android 4.0/4.1 compatibility fixes
* increased API level to 15 (Android 4.0.3) for TransactionTooLargeException

Version 1.3.2

General:
* show progress bar when synchronization is active
* minor bug/crash fixes and improvements

CalDAV:
* retain unknown iCalendar (VEVENT/VTODO) properties (max. 25 kB)
* query email address of user and use it as account name, if possible
* increase SEQUENCE when an event exception is changed
* only increase SEQEUENCE of events when we're ORGANIZER