diff --git a/appinfo/database.xml b/appinfo/database.xml
index 91c9076ba..a96137c42 100644
--- a/appinfo/database.xml
+++ b/appinfo/database.xml
@@ -46,6 +46,13 @@
                 <notnull>false</notnull>
                 <unsigned>true</unsigned>
             </field>
+            <field>
+                <name>last_modified</name>
+                <type>integer</type>
+                <default></default>
+                <notnull>false</notnull>
+                <unsigned>true</unsigned>
+            </field>
         </declaration>
     </table>
     <table>
@@ -85,6 +92,13 @@
                 <notnull>false</notnull>
                 <unsigned>true</unsigned>
             </field>
+            <field>
+                <name>last_modified</name>
+                <type>integer</type>
+                <default></default>
+                <notnull>false</notnull>
+                <unsigned>true</unsigned>
+            </field>
             <index>
                 <name>deck_stacks_board_id_index</name>
                 <field>
diff --git a/lib/Controller/BoardApiController.php b/lib/Controller/BoardApiController.php
index d45644eef..9ee8db431 100644
--- a/lib/Controller/BoardApiController.php
+++ b/lib/Controller/BoardApiController.php
@@ -24,6 +24,7 @@
 
 namespace OCA\Deck\Controller;
 
+use OCA\Deck\Db\ChangeHelper;
 use OCP\AppFramework\ApiController;
 use OCP\AppFramework\Http;
 use OCP\AppFramework\Http\DataResponse;
@@ -60,9 +61,14 @@ class BoardApiController extends ApiController {
 	 * Return all of the boards that the current user has access to.
 	 */
 	public function index() {
-		$boards = $this->service->findAll();
+		$modified = $this->request->getHeader('If-Modified-Since');
+		if ($modified === '') {
+			$boards = $this->service->findAll();
+		} else {
+			$boards = $this->service->findAll(strtotime($modified));
+		}
 		return new DataResponse($boards, HTTP::STATUS_OK);
-	}
+	 }
 
 	/**
 	 * @NoAdminRequired
@@ -87,8 +93,8 @@ class BoardApiController extends ApiController {
 	 *
 	 * Create a board with the specified title and color.
 	 */
-	public function create($title, $color) {		
-		$board = $this->service->create($title, $this->userId, $color);		
+	public function create($title, $color) {
+		$board = $this->service->create($title, $this->userId, $color);
 		return new DataResponse($board, HTTP::STATUS_OK);
 	}
 
@@ -96,14 +102,14 @@ class BoardApiController extends ApiController {
 	 * @NoAdminRequired
 	 * @CORS
 	 * @NoCSRFRequired
-	 *	 
+	 *
 	 * @params $title
-	 * @params $color	
-	 * @params $archived 
+	 * @params $color
+	 * @params $archived
 	 *
 	 * Update a board with the specified boardId, title and color, and archived state.
 	 */
-	public function update($title, $color, $archived = false) {		
+	public function update($title, $color, $archived = false) {
 		$board = $this->service->update($this->request->getParam('boardId'), $title, $color, $archived);
 		return new DataResponse($board, HTTP::STATUS_OK);
 	}
@@ -112,7 +118,7 @@ class BoardApiController extends ApiController {
 	 * @NoAdminRequired
 	 * @CORS
 	 * @NoCSRFRequired
-	 *	 
+	 *
 	 *
 	 * Delete the board specified by $boardId.  Return the board that was deleted.
 	 */
@@ -125,12 +131,12 @@ class BoardApiController extends ApiController {
 	 * @NoAdminRequired
 	 * @CORS
 	 * @NoCSRFRequired
-	 *	 
+	 *
 	 *
 	 * Undo the deletion of the board specified by $boardId.
 	 */
-	public function undoDelete() {		
-		$board = $this->service->deleteUndo($this->request->getParam('boardId'));		
+	public function undoDelete() {
+		$board = $this->service->deleteUndo($this->request->getParam('boardId'));
 		return new DataResponse($board, HTTP::STATUS_OK);
 	}
 
diff --git a/lib/Controller/CardApiController.php b/lib/Controller/CardApiController.php
index 5aa45d0f6..d1a4a8edc 100644
--- a/lib/Controller/CardApiController.php
+++ b/lib/Controller/CardApiController.php
@@ -23,6 +23,7 @@
 
  namespace OCA\Deck\Controller;
 
+ use OCA\Deck\Db\ChangeHelper;
  use OCP\AppFramework\ApiController;
  use OCP\AppFramework\Http;
  use OCP\AppFramework\Http\DataResponse;
@@ -35,8 +36,8 @@
  * @package OCA\Deck\Controller
  */
 class CardApiController extends ApiController {
-	private $cardService;		
-	private $userId;	
+	private $cardService;
+	private $userId;
 
 	/**
 	 * @param string $appName
@@ -45,9 +46,9 @@ class CardApiController extends ApiController {
 	 * @param $userId
 	 */
 	public function __construct($appName, IRequest $request, CardService $cardService, $userId) {
-		parent::__construct($appName, $request);		
-		$this->cardService = $cardService;		
-		$this->userId = $userId;		
+		parent::__construct($appName, $request);
+		$this->cardService = $cardService;
+		$this->userId = $userId;
 	}
 
 	/**
@@ -118,8 +119,8 @@ class CardApiController extends ApiController {
 	/**
 	 * @NoAdminRequired
 	 * @CORS
-	 * @NoCSRFRequired	 	 
-	 * 
+	 * @NoCSRFRequired
+	 *
 	 * Assign a label to a card.
 	 */
 	public function removeLabel($labelId) {
@@ -130,8 +131,8 @@ class CardApiController extends ApiController {
 	/**
 	 * @NoAdminRequired
 	 * @CORS
-	 * @NoCSRFRequired	 	 
-	 * 
+	 * @NoCSRFRequired
+	 *
 	 * Unassign a label to a card.
 	 */
 	public function unassignUser($userId) {
@@ -147,12 +148,12 @@ class CardApiController extends ApiController {
 	/**
 	 * @NoAdminRequired
 	 * @CORS
-	 * @NoCSRFRequired	 	 
-	 * 
+	 * @NoCSRFRequired
+	 *
 	 * Unassign a label to a card.
 	 */
 	public function reorder($stackId, $order) {
 		$card = $this->cardService->reorder($this->request->getParam('cardId'), $stackId, $order);
 		return new DataResponse($card, HTTP::STATUS_OK);
 	}
-}
\ No newline at end of file
+}
diff --git a/lib/Controller/StackApiController.php b/lib/Controller/StackApiController.php
index 6e4fb3867..021fae9c2 100644
--- a/lib/Controller/StackApiController.php
+++ b/lib/Controller/StackApiController.php
@@ -49,7 +49,7 @@ class StackApiController extends ApiController {
 	public function __construct($appName, IRequest $request, StackService $stackService, BoardService $boardService) {
 		parent::__construct($appName, $request);
 		$this->stackService = $stackService;
-		$this->boardService = $boardService;		
+		$this->boardService = $boardService;
 	}
 
 	/**
@@ -59,8 +59,13 @@ class StackApiController extends ApiController {
 	 *
 	 * Return all of the stacks in the specified board.
 	 */
-	public function index() {				
-		$stacks = $this->stackService->findAll($this->request->getParam('boardId'));
+	public function index() {
+		$since = 0;
+		$modified = $this->request->getHeader('If-Modified-Since');
+		if ($modified !== '') {
+			$since = strtotime($modified);
+		}
+		$stacks = $this->stackService->findAll($this->request->getParam('boardId'), $since);
 		return new DataResponse($stacks, HTTP::STATUS_OK);
 	}
 
@@ -75,7 +80,7 @@ class StackApiController extends ApiController {
 		$stack = $this->stackService->find($this->request->getParam('stackId'));
 		return new DataResponse($stack, HTTP::STATUS_OK);
 	}
-	
+
 	/**
 	 * @NoAdminRequired
 	 * @CORS
@@ -95,13 +100,13 @@ class StackApiController extends ApiController {
 	 * @NoAdminRequired
 	 * @CORS
 	 * @NoCSRFRequired
-	 *	 
-	 * @params $title	 
+	 *
+	 * @params $title
 	 * @params $order
 	 *
 	 * Update a stack by the specified stackId and boardId with the values that were put.
 	 */
-	public function update($title, $order) {		
+	public function update($title, $order) {
 		$stack = $this->stackService->update($this->request->getParam('stackId'), $title, $this->request->getParam('boardId'), $order, 0);
 		return new DataResponse($stack, HTTP::STATUS_OK);
 	}
@@ -113,7 +118,7 @@ class StackApiController extends ApiController {
 	 *
 	 * Delete the stack specified by $this->request->getParam('stackId').
 	 */
-	public function delete() {				
+	public function delete() {
 		$stack = $this->stackService->delete($this->request->getParam('stackId'));
 		return new DataResponse($stack, HTTP::STATUS_OK);
 	}
diff --git a/lib/Db/Board.php b/lib/Db/Board.php
index 905c4af62..fabf39061 100644
--- a/lib/Db/Board.php
+++ b/lib/Db/Board.php
@@ -5,20 +5,20 @@
  * @author Julius Härtl <jus@bitgrid.net>
  *
  * @license GNU AGPL version 3 or any later version
- *  
+ *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU Affero General Public License as
  *  published by the Free Software Foundation, either version 3 of the
  *  License, or (at your option) any later version.
- *  
+ *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU Affero General Public License for more details.
- *  
+ *
  *  You should have received a copy of the GNU Affero General Public License
  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *  
+ *
  */
 
 namespace OCA\Deck\Db;
@@ -35,12 +35,14 @@ class Board extends RelationalEntity {
 	protected $users = [];
 	protected $shared;
 	protected $deletedAt = 0;
+	protected $lastModified = 0;
 
 	public function __construct() {
 		$this->addType('id', 'integer');
 		$this->addType('shared', 'integer');
 		$this->addType('archived', 'boolean');
 		$this->addType('deletedAt', 'integer');
+		$this->addType('lastModified', 'integer');
 		$this->addRelation('labels');
 		$this->addRelation('acl');
 		$this->addRelation('shared');
@@ -75,4 +77,4 @@ class Board extends RelationalEntity {
 			$this->acl[$a->id] = $a;
 		}
 	}
-}
\ No newline at end of file
+}
diff --git a/lib/Db/BoardMapper.php b/lib/Db/BoardMapper.php
index 594c9b8ce..fddff1ac6 100644
--- a/lib/Db/BoardMapper.php
+++ b/lib/Db/BoardMapper.php
@@ -62,7 +62,7 @@ class BoardMapper extends DeckMapper implements IPermissionMapper {
 	 * @throws DoesNotExistException
 	 */
 	public function find($id, $withLabels = false, $withAcl = false) {
-		$sql = 'SELECT id, title, owner, color, archived, deleted_at FROM `*PREFIX*deck_boards` ' .
+		$sql = 'SELECT id, title, owner, color, archived, deleted_at, last_modified FROM `*PREFIX*deck_boards` ' .
 			'WHERE `id` = ?';
 		$board = $this->findEntity($sql, [$id]);
 
@@ -89,11 +89,14 @@ class BoardMapper extends DeckMapper implements IPermissionMapper {
 	 * @param null $offset
 	 * @return array
 	 */
-	public function findAllByUser($userId, $limit = null, $offset = null) {
-		$sql = 'SELECT id, title, owner, color, archived, deleted_at, 0 as shared FROM `*PREFIX*deck_boards` WHERE owner = ? UNION ' .
-			'SELECT boards.id, title, owner, color, archived, deleted_at, 1 as shared FROM `*PREFIX*deck_boards` as boards ' .
-			'JOIN `*PREFIX*deck_board_acl` as acl ON boards.id=acl.board_id WHERE acl.participant=? AND acl.type=? AND boards.owner != ?';
-		$entries = $this->findEntities($sql, [$userId, $userId, Acl::PERMISSION_TYPE_USER, $userId], $limit, $offset);
+	public function findAllByUser($userId, $limit = null, $offset = null, $since = 0) {
+		$sql = 'SELECT id, title, owner, color, archived, deleted_at, 0 as shared, last_modified FROM `*PREFIX*deck_boards` WHERE owner = ? AND last_modified > ?';
+		$entries = $this->findEntities($sql, [$userId, $since], $limit, $offset);
+
+		$sql = 'SELECT id, title, owner, color, archived, deleted_at, 0 as shared, last_modified FROM `*PREFIX*deck_boards` WHERE owner = ? AND last_modified > ? UNION ' .
+			'SELECT boards.id, title, owner, color, archived, deleted_at, 1 as shared, last_modified FROM `*PREFIX*deck_boards` as boards ' .
+			'JOIN `*PREFIX*deck_board_acl` as acl ON boards.id=acl.board_id WHERE acl.participant=? AND acl.type=? AND boards.owner != ? AND last_modified > ?';
+		$entries = $this->findEntities($sql, [$userId, $since, $userId, Acl::PERMISSION_TYPE_USER, $userId, $since], $limit, $offset);
 		/* @var Board $entry */
 		foreach ($entries as $entry) {
 			$acl = $this->aclMapper->findAll($entry->id);
@@ -115,7 +118,7 @@ class BoardMapper extends DeckMapper implements IPermissionMapper {
 		if (count($groups) <= 0) {
 			return [];
 		}
-		$sql = 'SELECT boards.id, title, owner, color, archived, deleted_at, 2 as shared FROM `*PREFIX*deck_boards` as boards ' .
+		$sql = 'SELECT boards.id, title, owner, color, archived, deleted_at, 2 as shared, last_modified FROM `*PREFIX*deck_boards` as boards ' .
 			'INNER JOIN `*PREFIX*deck_board_acl` as acl ON boards.id=acl.board_id WHERE owner != ? AND type=? AND (';
 		for ($i = 0, $iMax = count($groups); $i < $iMax; $i++) {
 			$sql .= 'acl.participant = ? ';
@@ -141,7 +144,7 @@ class BoardMapper extends DeckMapper implements IPermissionMapper {
 	public function findToDelete() {
 		// add buffer of 5 min
 		$timeLimit = time() - (60 * 5);
-		$sql = 'SELECT id, title, owner, color, archived, deleted_at FROM `*PREFIX*deck_boards` ' .
+		$sql = 'SELECT id, title, owner, color, archived, deleted_at, last_modified FROM `*PREFIX*deck_boards` ' .
 			'WHERE `deleted_at` > 0 AND `deleted_at` < ?';
 		return $this->findEntities($sql, [$timeLimit]);
 	}
diff --git a/lib/Db/CardMapper.php b/lib/Db/CardMapper.php
index 31f363398..9cbcc49b6 100644
--- a/lib/Db/CardMapper.php
+++ b/lib/Db/CardMapper.php
@@ -118,10 +118,10 @@ class CardMapper extends DeckMapper implements IPermissionMapper {
 		return $card;
 	}
 
-	public function findAll($stackId, $limit = null, $offset = null) {
+	public function findAll($stackId, $limit = null, $offset = null, $since = -1) {
 		$sql = 'SELECT * FROM `*PREFIX*deck_cards` 
-          WHERE `stack_id` = ? AND NOT archived AND deleted_at = 0 ORDER BY `order`';
-		return $this->findEntities($sql, [$stackId], $limit, $offset);
+          WHERE `stack_id` = ? AND NOT archived AND deleted_at = 0 AND last_modified > ? ORDER BY `order`';
+		return $this->findEntities($sql, [$stackId, $since], $limit, $offset);
 	}
 
 	public function findDeleted($boardId, $limit = null, $offset = null) {
diff --git a/lib/Db/Stack.php b/lib/Db/Stack.php
index f1ba66c9c..9c5eb4bf9 100644
--- a/lib/Db/Stack.php
+++ b/lib/Db/Stack.php
@@ -30,11 +30,13 @@ class Stack extends RelationalEntity {
 	protected $deletedAt = 0;
 	protected $cards = array();
 	protected $order;
+	protected $lastModified = 0;
 
 	public function __construct() {
 		$this->addType('id', 'integer');
 		$this->addType('boardId', 'integer');
 		$this->addType('deletedAt', 'integer');
+		$this->addType('lastModified', 'integer');
 		$this->addType('order', 'integer');
 	}
 
diff --git a/lib/Service/AttachmentService.php b/lib/Service/AttachmentService.php
index 8c7a81307..58681a4d5 100644
--- a/lib/Service/AttachmentService.php
+++ b/lib/Service/AttachmentService.php
@@ -31,6 +31,7 @@ use OCA\Deck\Db\Acl;
 use OCA\Deck\Db\Attachment;
 use OCA\Deck\Db\AttachmentMapper;
 use OCA\Deck\Db\CardMapper;
+use OCA\Deck\Db\ChangeHelper;
 use OCA\Deck\InvalidAttachmentType;
 use OCA\Deck\NoPermissionException;
 use OCA\Deck\NotFoundException;
@@ -69,7 +70,7 @@ class AttachmentService {
 	 * @param IL10N $l10n
 	 * @throws \OCP\AppFramework\QueryException
 	 */
-	public function __construct(AttachmentMapper $attachmentMapper, CardMapper $cardMapper, PermissionService $permissionService, Application $application, ICacheFactory $cacheFactory, $userId, IL10N $l10n, ActivityManager $activityManager) {
+	public function __construct(AttachmentMapper $attachmentMapper, CardMapper $cardMapper, ChangeHelper $changeHelper, PermissionService $permissionService, Application $application, ICacheFactory $cacheFactory, $userId, IL10N $l10n, ActivityManager $activityManager) {
 		$this->attachmentMapper = $attachmentMapper;
 		$this->cardMapper = $cardMapper;
 		$this->permissionService = $permissionService;
@@ -78,6 +79,7 @@ class AttachmentService {
 		$this->cache = $cacheFactory->createDistributed('deck-card-attachments-');
 		$this->l10n = $l10n;
 		$this->activityManager = $activityManager;
+		$this->changeHelper = $changeHelper;
 
 		// Register shipped attachment services
 		// TODO: move this to a plugin based approach once we have different types of attachments
@@ -205,6 +207,7 @@ class AttachmentService {
 		} catch (InvalidAttachmentType $e) {
 			// just store the data
 		}
+		$this->changeHelper->cardChanged($attachment->getCardId());
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $attachment, ActivityManager::SUBJECT_ATTACHMENT_CREATE);
 		return $attachment;
 	}
@@ -290,6 +293,7 @@ class AttachmentService {
 		} catch (InvalidAttachmentType $e) {
 			// just store the data
 		}
+		$this->changeHelper->cardChanged($attachment->getCardId());
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $attachment, ActivityManager::SUBJECT_ATTACHMENT_UPDATE);
 		return $attachment;
 	}
@@ -332,6 +336,7 @@ class AttachmentService {
 			// just delete without further action
 		}
 		$attachment = $this->attachmentMapper->delete($attachment);
+		$this->changeHelper->cardChanged($attachment->getCardId());
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $attachment, ActivityManager::SUBJECT_ATTACHMENT_DELETE);
 		return $attachment;
 	}
@@ -355,6 +360,7 @@ class AttachmentService {
 			if ($service->allowUndo()) {
 				$attachment->setDeletedAt(0);
 				$attachment = $this->attachmentMapper->update($attachment);
+				$this->changeHelper->cardChanged($attachment->getCardId());
 				$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $attachment, ActivityManager::SUBJECT_ATTACHMENT_RESTORE);
 				return $attachment;
 			}
diff --git a/lib/Service/BoardService.php b/lib/Service/BoardService.php
index b421a46d8..e365fd583 100644
--- a/lib/Service/BoardService.php
+++ b/lib/Service/BoardService.php
@@ -84,10 +84,10 @@ class BoardService {
 	/**
 	 * @return array
 	 */
-	public function findAll() {
+	public function findAll($since = 0) {
 		$userInfo = $this->getBoardPrerequisites();
-		$userBoards = $this->boardMapper->findAllByUser($userInfo['user']);
-		$groupBoards = $this->boardMapper->findAllByGroups($userInfo['user'], $userInfo['groups']);
+		$userBoards = $this->boardMapper->findAllByUser($userInfo['user'], null, null, $since);
+		$groupBoards = $this->boardMapper->findAllByGroups($userInfo['user'], $userInfo['groups'],null, null,  $since);
 		$complete = array_merge($userBoards, $groupBoards);
 		$result = [];
 		foreach ($complete as &$item) {
diff --git a/lib/Service/CardService.php b/lib/Service/CardService.php
index 0cf6cfa60..1bebfa282 100644
--- a/lib/Service/CardService.php
+++ b/lib/Service/CardService.php
@@ -30,6 +30,7 @@ use OCA\Deck\Db\AssignedUsersMapper;
 use OCA\Deck\Db\Card;
 use OCA\Deck\Db\CardMapper;
 use OCA\Deck\Db\Acl;
+use OCA\Deck\Db\ChangeHelper;
 use OCA\Deck\Db\StackMapper;
 use OCA\Deck\Notification\NotificationHelper;
 use OCA\Deck\Db\BoardMapper;
@@ -54,6 +55,7 @@ class CardService {
 	private $currentUser;
 	private $activityManager;
 	private $commentsManager;
+	private $changeHelper;
 
 	public function __construct(
 		CardMapper $cardMapper,
@@ -68,6 +70,7 @@ class CardService {
 		ActivityManager $activityManager,
 		ICommentsManager $commentsManager,
 		IUserManager $userManager,
+		ChangeHelper $changeHelper,
 		$userId
 	) {
 		$this->cardMapper = $cardMapper;
@@ -82,6 +85,7 @@ class CardService {
 		$this->activityManager = $activityManager;
 		$this->commentsManager = $commentsManager;
 		$this->userManager = $userManager;
+		$this->changeHelper = $changeHelper;
 		$this->currentUser = $userId;
 	}
 
@@ -176,6 +180,7 @@ class CardService {
 		$card->setOwner($owner);
 		$card = $this->cardMapper->insert($card);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $card, ActivityManager::SUBJECT_CARD_CREATE);
+		$this->changeHelper->cardChanged($card->getId(), false);
 		return $card;
 	}
 
@@ -202,6 +207,7 @@ class CardService {
 		$card->setDeletedAt(time());
 		$this->cardMapper->update($card);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $card, ActivityManager::SUBJECT_CARD_DELETE);
+		$this->changeHelper->cardChanged($card->getId(), false);
 		return $card;
 	}
 
@@ -263,6 +269,7 @@ class CardService {
 		$changes->setAfter($card);
 		$card = $this->cardMapper->update($card);
 		$this->activityManager->triggerUpdateEvents(ActivityManager::DECK_OBJECT_CARD, $changes, ActivityManager::SUBJECT_CARD_UPDATE);
+		$this->changeHelper->cardChanged($card->getId(), false);
 		return $card;
 	}
 
@@ -295,6 +302,7 @@ class CardService {
 			throw new StatusException('Operation not allowed. This card is archived.');
 		}
 		$card->setTitle($title);
+		$this->changeHelper->cardChanged($card->getId(), false);
 		return $this->cardMapper->update($card);
 	}
 
@@ -349,7 +357,7 @@ class CardService {
 			$this->cardMapper->update($card);
 			$result[$card->getOrder()] = $card;
 		}
-
+		$this->changeHelper->cardChanged($id, false);
 		return $result;
 	}
 
@@ -376,6 +384,7 @@ class CardService {
 		$card->setArchived(true);
 		$newCard = $this->cardMapper->update($card);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $newCard, ActivityManager::SUBJECT_CARD_UPDATE_ARCHIVE);
+		$this->changeHelper->cardChanged($id, false);
 		return $newCard;
 	}
 
@@ -402,6 +411,7 @@ class CardService {
 		$card->setArchived(false);
 		$newCard = $this->cardMapper->update($card);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $newCard, ActivityManager::SUBJECT_CARD_UPDATE_UNARCHIVE);
+		$this->changeHelper->cardChanged($id, false);
 		return $newCard;
 	}
 
@@ -434,6 +444,7 @@ class CardService {
 		}
 		$label = $this->labelMapper->find($labelId);
 		$this->cardMapper->assignLabel($cardId, $labelId);
+		$this->changeHelper->cardChanged($cardId, false);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $card, ActivityManager::SUBJECT_LABEL_ASSIGN, ['label' => $label]);
 	}
 
@@ -466,6 +477,7 @@ class CardService {
 		}
 		$label = $this->labelMapper->find($labelId);
 		$this->cardMapper->removeLabel($cardId, $labelId);
+		$this->changeHelper->cardChanged($cardId, false);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $card, ActivityManager::SUBJECT_LABEL_UNASSING, ['label' => $label]);
 	}
 
@@ -505,6 +517,7 @@ class CardService {
 		$assignment->setCardId($cardId);
 		$assignment->setParticipant($userId);
 		$assignment = $this->assignedUsersMapper->insert($assignment);
+		$this->changeHelper->cardChanged($cardId, false);
 		$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $card, ActivityManager::SUBJECT_CARD_USER_ASSIGN, ['assigneduser' => $userId]);
 		return $assignment;
 	}
@@ -535,6 +548,7 @@ class CardService {
 				$assignment = $this->assignedUsersMapper->delete($assignment);
 				$card = $this->cardMapper->find($cardId);
 				$this->activityManager->triggerEvent(ActivityManager::DECK_OBJECT_CARD, $card, ActivityManager::SUBJECT_CARD_USER_UNASSIGN, ['assigneduser' => $userId]);
+				$this->changeHelper->cardChanged($cardId, false);
 				return $assignment;
 			}
 		}
diff --git a/lib/Service/StackService.php b/lib/Service/StackService.php
index 0ee599133..cbefec749 100644
--- a/lib/Service/StackService.php
+++ b/lib/Service/StackService.php
@@ -74,10 +74,10 @@ class StackService {
 		$this->activityManager = $activityManager;
 	}
 
-	private function enrichStackWithCards($stack) {
-		$cards = $this->cardMapper->findAll($stack->getId());
+	private function enrichStackWithCards($stack, $since = -1) {
+		$cards = $this->cardMapper->findAll($stack->getId(), null, null, $since);
 
-		if(is_null($cards)) {
+		if(\count($cards) === 0) {
 			return;
 		}
 
@@ -88,9 +88,9 @@ class StackService {
 		$stack->setCards($cards);
 	}
 
-	private function enrichStacksWithCards($stacks) {
+	private function enrichStacksWithCards($stacks, $since = -1) {
 		foreach ($stacks as $stack) {
-			$this->enrichStackWithCards($stack);
+			$this->enrichStackWithCards($stack, $since);
 		}
 	}
 
@@ -123,14 +123,14 @@ class StackService {
 	 * @throws \OCA\Deck\NoPermissionException
 	 * @throws BadRequestException
 	 */
-	public function findAll($boardId) {
+	public function findAll($boardId, $since = 0) {
 		if (is_numeric($boardId) === false) {
 			throw new BadRequestException('boardId must be a number');
 		}
 
 		$this->permissionService->checkPermission(null, $boardId, Acl::PERMISSION_READ);
 		$stacks = $this->stackMapper->findAll($boardId);
-		$this->enrichStacksWithCards($stacks);
+		$this->enrichStacksWithCards($stacks, $since);
 		return $stacks;
 	}