diff --git a/web/page_view.js b/web/page_view.js
index 86572cb89..109f0f515 100644
--- a/web/page_view.js
+++ b/web/page_view.js
@@ -353,7 +353,8 @@ var PageView = function pageView(container, id, scale, defaultViewport,
         return;
       }
       dest = null;
-      this.viewer.setScale(this.viewer.currentScaleValue, true, true);
+      // Fixes the case when PDF has different page sizes.
+      this.viewer.currentScaleValue = this.viewer.currentScaleValue;
     }
     if (!dest) {
       scrollIntoView(div);
@@ -413,9 +414,9 @@ var PageView = function pageView(container, id, scale, defaultViewport,
     }
 
     if (scale && scale !== this.viewer.currentScale) {
-      this.viewer.setScale(scale, true, true);
+      this.viewer.currentScaleValue = scale;
     } else if (this.viewer.currentScale === UNKNOWN_SCALE) {
-      this.viewer.setScale(DEFAULT_SCALE, true, true);
+      this.viewer.currentScaleValue = DEFAULT_SCALE;
     }
 
     if (scale === 'page-fit' && !dest[4]) {
diff --git a/web/pdf_viewer.js b/web/pdf_viewer.js
index 1ea61bb5a..9bbba0931 100644
--- a/web/pdf_viewer.js
+++ b/web/pdf_viewer.js
@@ -53,7 +53,7 @@ var PDFViewer = (function pdfViewer() {
     this.lastScroll = 0;
     this.updateInProgress = false;
     this.presentationModeState = PresentationModeState.UNKNOWN;
-    this.resetView();
+    this._resetView();
   }
 
   PDFViewer.prototype = {
@@ -65,28 +65,102 @@ var PDFViewer = (function pdfViewer() {
       return this.pages[index];
     },
 
-    setCurrentPageNumber: function (val) {
+    get currentPageNumber() {
+      return this._currentPageNumber;
+    },
+
+    set currentPageNumber(val) {
+      if (!this.pdfDocument) {
+        this._currentPageNumber = val;
+        return;
+      }
+
       var event = document.createEvent('UIEvents');
       event.initUIEvent('pagechange', true, true, window, 0);
       event.updateInProgress = this.updateInProgress;
 
       if (!(0 < val && val <= this.pagesCount)) {
-        this.previousPageNumber = val;
         event.pageNumber = this.page;
+        event.previousPageNumber = val;
         this.container.dispatchEvent(event);
         return;
       }
 
       this.pages[val - 1].updateStats();
-      this.previousPageNumber = this.currentPageNumber;
-      this.currentPageNumber = val;
+      event.previousPageNumber = this._currentPageNumber;
+      this._currentPageNumber = val;
       event.pageNumber = val;
       this.container.dispatchEvent(event);
     },
 
+    /**
+     * @returns {number}
+     */
+    get currentScale() {
+      return this._currentScale;
+    },
+
+    /**
+     * @param {number} val - Scale of the pages in percents.
+     */
+    set currentScale(val) {
+      if (isNaN(val))  {
+        throw new Error('Invalid numeric scale');
+      }
+      if (!this.pdfDocument) {
+        this._currentScale = val;
+        this._currentScaleValue = val.toString();
+        return;
+      }
+      this._setScale(val, false);
+    },
+
+    /**
+     * @returns {string}
+     */
+    get currentScaleValue() {
+      return this._currentScaleValue;
+    },
+
+    /**
+     * @param val - The scale of the pages (in percent or predefined value).
+     */
+    set currentScaleValue(val) {
+      if (!this.pdfDocument) {
+        this._currentScale = isNaN(val) ? UNKNOWN_SCALE : val;
+        this._currentScaleValue = val;
+        return;
+      }
+      this._setScale(val, false);
+    },
+
+    /**
+     * @returns {number}
+     */
+    get pagesRotation() {
+      return this._pagesRotation;
+    },
+
+    /**
+     * @param {number} rotation - The rotation of the pages (0, 90, 180, 270).
+     */
+    set pagesRotation(rotation) {
+      this._pagesRotation = rotation;
+
+      for (var i = 0, l = this.pages.length; i < l; i++) {
+        var page = this.pages[i];
+        page.update(page.scale, rotation);
+      }
+
+      this._setScale(this._currentScaleValue, true);
+    },
+
+    /**
+     * @param pdfDocument {PDFDocument}
+     */
     setDocument: function (pdfDocument) {
       if (this.pdfDocument) {
-        this.resetView();
+        this._resetView();
       }
 
       this.pdfDocument = pdfDocument;
@@ -139,7 +213,7 @@ var PDFViewer = (function pdfViewer() {
       // Fetch a single page so we can get a viewport that will be the default
       // viewport for all pages
       return firstPagePromise.then(function(pdfPage) {
-        var scale = this.currentScale || 1.0;
+        var scale = this._currentScale || 1.0;
         var viewport = pdfPage.getViewport(scale * CSS_UNITS);
         for (var pageNum = 1; pageNum <= pagesCount; ++pageNum) {
           var pageSource = new PDFPageSource(pdfDocument, pageNum);
@@ -183,14 +257,14 @@ var PDFViewer = (function pdfViewer() {
       }.bind(this));
     },
 
-    resetView: function () {
+    _resetView: function () {
       this.cache = new Cache(DEFAULT_CACHE_SIZE);
       this.pages = [];
-      this.currentPageNumber = 1;
-      this.previousPageNumber = 1;
-      this.currentScale = UNKNOWN_SCALE;
-      this.currentScaleValue = null;
+      this._currentPageNumber = 1;
+      this._currentScale = UNKNOWN_SCALE;
+      this._currentScaleValue = null;
       this.location = null;
+      this._pagesRotation = 0;
 
       var container = this.viewer;
       while (container.hasChildNodes()) {
@@ -208,18 +282,18 @@ var PDFViewer = (function pdfViewer() {
     },
 
     _setScaleUpdatePages: function pdfViewer_setScaleUpdatePages(
-        newScale, newValue, resetAutoSettings, noScroll, preset) {
-      this.currentScaleValue = newValue;
-      if (newScale === this.currentScale) {
+        newScale, newValue, noScroll, preset) {
+      this._currentScaleValue = newValue;
+      if (newScale === this._currentScale) {
         return;
       }
       for (var i = 0, ii = this.pages.length; i < ii; i++) {
         this.pages[i].update(newScale);
       }
-      this.currentScale = newScale;
+      this._currentScale = newScale;
 
       if (!noScroll) {
-        var page = this.currentPageNumber, dest;
+        var page = this._currentPageNumber, dest;
         var inPresentationMode =
           this.presentationModeState === PresentationModeState.CHANGING ||
           this.presentationModeState === PresentationModeState.FULLSCREEN;
@@ -235,23 +309,22 @@ var PDFViewer = (function pdfViewer() {
       var event = document.createEvent('UIEvents');
       event.initUIEvent('scalechange', true, true, window, 0);
       event.scale = newScale;
-      event.resetAutoSettings = resetAutoSettings;
       if (preset) {
         event.presetValue = newValue;
       }
       this.container.dispatchEvent(event);
     },
 
-    setScale: function pdfViewer_setScale(value, resetAutoSettings, noScroll) {
+    _setScale: function pdfViewer_setScale(value, noScroll) {
       if (value === 'custom') {
         return;
       }
       var scale = parseFloat(value);
 
       if (scale > 0) {
-        this._setScaleUpdatePages(scale, value, true, noScroll, false);
+        this._setScaleUpdatePages(scale, value, noScroll, false);
       } else {
-        var currentPage = this.pages[this.currentPageNumber - 1];
+        var currentPage = this.pages[this._currentPageNumber - 1];
         if (!currentPage) {
           return;
         }
@@ -287,23 +360,13 @@ var PDFViewer = (function pdfViewer() {
               '\' is an unknown zoom value.');
             return;
         }
-        this._setScaleUpdatePages(scale, value, resetAutoSettings, noScroll,
-                                  true);
+        this._setScaleUpdatePages(scale, value, noScroll, true);
       }
     },
 
-    updateRotation: function pdfViewRotatePages(rotation) {
-      for (var i = 0, l = this.pages.length; i < l; i++) {
-        var page = this.pages[i];
-        page.update(page.scale, rotation);
-      }
-
-      this.setScale(this.currentScaleValue, true, true);
-    },
-
-    updateLocation: function (firstPage) {
-      var currentScale = this.currentScale;
-      var currentScaleValue = this.currentScaleValue;
+    _updateLocation: function (firstPage) {
+      var currentScale = this._currentScale;
+      var currentScaleValue = this._currentScaleValue;
       var normalizedScaleValue =
         parseFloat(currentScaleValue) === currentScale ?
         Math.round(currentScale * 10000) / 100 : currentScaleValue;
@@ -330,7 +393,7 @@ var PDFViewer = (function pdfViewer() {
     },
 
     update: function () {
-      var visible = this.getVisiblePages();
+      var visible = this._getVisiblePages();
       var visiblePages = visible.views;
       if (visiblePages.length === 0) {
         return;
@@ -354,7 +417,7 @@ var PDFViewer = (function pdfViewer() {
         if (page.percent < 100) {
           break;
         }
-        if (page.id === this.currentPageNumber) {
+        if (page.id === currentId) {
           stillFullyVisible = true;
           break;
         }
@@ -365,10 +428,10 @@ var PDFViewer = (function pdfViewer() {
       }
 
       if (this.presentationModeState !== PresentationModeState.FULLSCREEN) {
-        this.setCurrentPageNumber(currentId);
+        this.currentPageNumber = currentId;
       }
 
-      this.updateLocation(firstPage);
+      this._updateLocation(firstPage);
 
       this.updateInProgress = false;
 
@@ -394,14 +457,14 @@ var PDFViewer = (function pdfViewer() {
         false : (this.container.scrollWidth > this.container.clientWidth));
     },
 
-    getVisiblePages: function () {
+    _getVisiblePages: function () {
       if (this.presentationModeState !== PresentationModeState.FULLSCREEN) {
         return getVisibleElements(this.container, this.pages, true);
       } else {
         // The algorithm in getVisibleElements doesn't work in all browsers and
         // configurations when presentation mode is active.
         var visible = [];
-        var currentPage = this.pages[this.currentPageNumber - 1];
+        var currentPage = this.pages[this._currentPageNumber - 1];
         visible.push({ id: currentPage.id, view: currentPage });
         return { first: currentPage, last: currentPage, views: visible };
       }
@@ -417,7 +480,7 @@ var PDFViewer = (function pdfViewer() {
     },
 
     forceRendering: function (currentlyVisiblePages) {
-      var visiblePages = currentlyVisiblePages || this.getVisiblePages();
+      var visiblePages = currentlyVisiblePages || this._getVisiblePages();
       var pageView = this.renderingQueue.getHighestPriority(visiblePages,
                                                             this.pages,
                                                             this.scroll.down);
diff --git a/web/thumbnail_view.js b/web/thumbnail_view.js
index 313b2339d..205e31fd6 100644
--- a/web/thumbnail_view.js
+++ b/web/thumbnail_view.js
@@ -247,13 +247,12 @@ var PDFThumbnailViewer = (function pdfThumbnailViewer() {
     this.renderingQueue = options.renderingQueue;
     this.linkService = options.linkService;
 
-    this.scroll = watchScroll(this.container, this.scrollUpdated.bind(this));
-    this.thumbnails = [];
-    this.currentPage = -1;
+    this.scroll = watchScroll(this.container, this._scrollUpdated.bind(this));
+    this._resetView();
   }
 
   PDFThumbnailViewer.prototype = {
-    scrollUpdated: function PDFThumbnailViewer_scrollUpdated() {
+    _scrollUpdated: function PDFThumbnailViewer_scrollUpdated() {
       this.renderingQueue.renderHighestPriority();
     },
 
@@ -261,18 +260,18 @@ var PDFThumbnailViewer = (function pdfThumbnailViewer() {
       return this.thumbnails[index];
     },
 
-    getVisibleThumbs: function PDFThumbnailViewer_getVisibleThumbs() {
+    _getVisibleThumbs: function PDFThumbnailViewer_getVisibleThumbs() {
       return getVisibleElements(this.container, this.thumbnails);
     },
 
-    updatePage: function (page) {
+    scrollThumbnailIntoView: function (page) {
       var selected = document.querySelector('.thumbnail.selected');
       if (selected) {
         selected.classList.remove('selected');
       }
       var thumbnail = document.getElementById('thumbnailContainer' + page);
       thumbnail.classList.add('selected');
-      var visibleThumbs = this.getVisibleThumbs();
+      var visibleThumbs = this._getVisibleThumbs();
       var numVisibleThumbs = visibleThumbs.views.length;
 
       // If the thumbnail isn't currently visible, scroll it into view.
@@ -284,13 +283,17 @@ var PDFThumbnailViewer = (function pdfThumbnailViewer() {
           scrollIntoView(thumbnail, { top: THUMBNAIL_SCROLL_MARGIN });
         }
       }
-      this.currentPage = page;
     },
 
-    updateRotation: function (pageRotation) {
+    get pagesRotation() {
+      return this._pagesRotation;
+    },
+
+    set pagesRotation(rotation) {
+      this._pagesRotation = rotation;
       for (var i = 0, l = this.thumbnails.length; i < l; i++) {
         var thumb = this.thumbnails[i];
-        thumb.update(pageRotation);
+        thumb.update(rotation);
       }
     },
 
@@ -298,6 +301,11 @@ var PDFThumbnailViewer = (function pdfThumbnailViewer() {
       ThumbnailView.tempImageCache = null;
     },
 
+    _resetView: function () {
+      this.thumbnails = [];
+      this._pagesRotation = 0;
+    },
+
     setDocument: function (pdfDocument) {
       if (this.pdfDocument) {
         // cleanup of the elements and views
@@ -305,7 +313,7 @@ var PDFThumbnailViewer = (function pdfThumbnailViewer() {
         while (thumbsView.hasChildNodes()) {
           thumbsView.removeChild(thumbsView.lastChild);
         }
-        this.thumbnails = [];
+        this._resetView();
       }
 
       this.pdfDocument = pdfDocument;
@@ -334,7 +342,7 @@ var PDFThumbnailViewer = (function pdfThumbnailViewer() {
     },
 
     forceRendering: function () {
-      var visibleThumbs = this.getVisibleThumbs();
+      var visibleThumbs = this._getVisibleThumbs();
       var thumbView = this.renderingQueue.getHighestPriority(visibleThumbs,
                                                              this.thumbnails,
                                                              this.scroll.down);
diff --git a/web/viewer.js b/web/viewer.js
index 3d93ea964..99f277a57 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -96,6 +96,7 @@ var PDFView = {
   pdfThumbnailViewer: null,
   pdfRenderingQueue: null,
   pageRotation: 0,
+  updateScaleControls: true,
   mouseScrollTimeStamp: 0,
   mouseScrollDelta: 0,
   isViewerEmbedded: (window.parent !== window),
@@ -258,7 +259,7 @@ var PDFView = {
       newScale = Math.ceil(newScale * 10) / 10;
       newScale = Math.min(MAX_SCALE, newScale);
     } while (--ticks && newScale < MAX_SCALE);
-    this.pdfViewer.setScale(newScale, true);
+    this.setScale(newScale, true);
   },
 
   zoomOut: function pdfViewZoomOut(ticks) {
@@ -268,7 +269,7 @@ var PDFView = {
       newScale = Math.floor(newScale * 10) / 10;
       newScale = Math.max(MIN_SCALE, newScale);
     } while (--ticks && newScale > MIN_SCALE);
-    this.pdfViewer.setScale(newScale, true);
+    this.setScale(newScale, true);
   },
 
   get currentScaleValue() {
@@ -280,7 +281,7 @@ var PDFView = {
   },
 
   set page(val) {
-    this.pdfViewer.setCurrentPageNumber(val);
+    this.pdfViewer.currentPageNumber = val;
   },
 
   get page() {
@@ -825,6 +826,7 @@ var PDFView = {
 
   load: function pdfViewLoad(pdfDocument, scale) {
     var self = this;
+    scale = scale || UNKNOWN_SCALE;
 
     PDFView.findController.reset();
 
@@ -1061,14 +1063,14 @@ var PDFView = {
     } else if (storedHash) {
       this.setHash(storedHash);
     } else if (scale) {
-      this.pdfViewer.setScale(scale, true);
+      this.setScale(scale, true);
       this.page = 1;
     }
 
     if (PDFView.pdfViewer.currentScale === UNKNOWN_SCALE) {
       // Scale was not initialized: invalid bookmark or scale was not specified.
       // Setting the default one.
-      this.pdfViewer.setScale(DEFAULT_SCALE, true);
+      this.setScale(DEFAULT_SCALE, true);
     }
   },
 
@@ -1270,16 +1272,18 @@ var PDFView = {
     this.forceRendering();
   },
 
-  setScale: function (value, resetAutoSettings, noScroll) {
-    this.pdfViewer.setScale(value, resetAutoSettings, noScroll);
+  setScale: function (value, resetAutoSettings) {
+    this.updateScaleControls = !!resetAutoSettings;
+    this.pdfViewer.currentScaleValue = value;
+    this.updateScaleControls = true;
   },
 
   rotatePages: function pdfViewRotatePages(delta) {
     var currentPage = this.getPageView(this.page - 1);
 
     this.pageRotation = (this.pageRotation + 360 + delta) % 360;
-    this.pdfViewer.updateRotation(this.pageRotation);
-    this.pdfThumbnailViewer.updateRotation(this.pageRotation);
+    this.pdfViewer.pagesRotation = this.pageRotation;
+    this.pdfThumbnailViewer.pagesRotation = this.pageRotation;
 
     this.forceRendering();
 
@@ -1590,7 +1594,7 @@ function webViewerInitialized() {
 
   document.getElementById('scaleSelect').addEventListener('change',
     function() {
-      PDFView.pdfViewer.setScale(this.value);
+      PDFView.setScale(this.value, false);
     });
 
   document.getElementById('presentationMode').addEventListener('click',
@@ -1730,7 +1734,7 @@ window.addEventListener('resize', function webViewerResize(evt) {
       (document.getElementById('pageWidthOption').selected ||
        document.getElementById('pageFitOption').selected ||
        document.getElementById('pageAutoOption').selected)) {
-    PDFView.pdfViewer.setScale(document.getElementById('scaleSelect').value);
+    PDFView.setScale(document.getElementById('scaleSelect').value, false);
   }
   updateViewarea();
 
@@ -1825,7 +1829,7 @@ window.addEventListener('scalechange', function scalechange(evt) {
   var customScaleOption = document.getElementById('customScaleOption');
   customScaleOption.selected = false;
 
-  if (!evt.resetAutoSettings &&
+  if (!PDFView.updateScaleControls &&
       (document.getElementById('pageWidthOption').selected ||
        document.getElementById('pageFitOption').selected ||
        document.getElementById('pageAutoOption').selected)) {
@@ -1849,9 +1853,9 @@ window.addEventListener('scalechange', function scalechange(evt) {
 
 window.addEventListener('pagechange', function pagechange(evt) {
   var page = evt.pageNumber;
-  if (PDFView.pdfViewer.previousPageNumber !== page) {
+  if (evt.previousPageNumber !== page) {
     document.getElementById('pageNumber').value = page;
-    PDFView.pdfThumbnailViewer.updatePage(page);
+    PDFView.pdfThumbnailViewer.scrollThumbnailIntoView(page);
   }
   var numPages = PDFView.pagesCount;
 
@@ -1948,7 +1952,7 @@ window.addEventListener('keydown', function keydown(evt) {
         // keeping it unhandled (to restore page zoom to 100%)
         setTimeout(function () {
           // ... and resetting the scale after browser adjusts its scale
-          PDFView.pdfViewer.setScale(DEFAULT_SCALE, true);
+          PDFView.setScale(DEFAULT_SCALE, true);
         });
         handled = false;
         break;