diff --git a/README.md b/README.md
index 8e21c7477b850e697020ae885abe7bdde83dd178..f2cdfa8ef25262d3cd625b6419c624fbb936edb6 100644
--- a/README.md
+++ b/README.md
@@ -5,12 +5,15 @@ Made just for fun. [Play it here!](http://gabrielecirulli.github.io/2048/)
 
 [![Screenshot](http://pictures.gabrielecirulli.com/2048-20140309-234100.png)](http://pictures.gabrielecirulli.com/2048-20140309-234100.png)
 
-That screenshot is fake by, the way. I never reached 2048 :smile:
+That screenshot is fake, by the way. I never reached 2048 :smile:
 
 ## Contributing
-Changes and improvements are more than welcome! Feel free to fork and open a pull request. Please make your changes in a specifically made branch and request to pull on `master`! If you can, please make sure the game fully works before sending the PR, as that will help speed up the process.
+Changes and improvements are more than welcome! Feel free to fork and open a pull request. Please make your changes in a specific branch and request to pull into `master`! If you can, please make sure the game fully works before sending the PR, as that will help speed up the process.
 
 You can find the same information in the [contributing guide.](https://github.com/gabrielecirulli/2048/blob/master/CONTRIBUTING.md)
 
 ## License
 2048 is licensed under the [MIT license.](https://github.com/gabrielecirulli/2048/blob/master/LICENSE.txt)
+
+## Donations
+I made this in my spare time, and it's hosted on GitHub (which means I don't have any hosting costs), but if you enjoyed the game and feel like buying me coffee, you can donate at my BTC address: `1Ec6onfsQmoP9kkL3zkpB6c5sA4PVcXU2i`. Thank you very much!
diff --git a/favicon.ico b/favicon.ico
new file mode 100644
index 0000000000000000000000000000000000000000..22109e04a9f44bde18ec7b7a4b7410d0246521bc
Binary files /dev/null and b/favicon.ico differ
diff --git a/index.html b/index.html
index cf017fc99fbaa58e48e1db9d28fbfda3f2cedd33..32c86ba07a50519e83fec6b45946c8d2b030ed09 100644
--- a/index.html
+++ b/index.html
@@ -5,15 +5,7 @@
   <title>2048</title>
 
   <link href="style/main.css" rel="stylesheet" type="text/css">
-
-  <script src="js/hammer.min.js"></script>
-  <script src="js/keyboard_input_manager.js"></script>
-  <script src="js/html_actuator.js"></script>
-  <script src="js/grid.js"></script>
-  <script src="js/tile.js"></script>
-  <script src="js/local_score_manager.js"></script>
-  <script src="js/game_manager.js"></script>
-  <script src="js/application.js"></script>
+  <link rel="shortcut icon" href="favicon.ico">
 
   <meta name="HandheldFriendly" content="True">
   <meta name="MobileOptimized" content="320">
@@ -75,8 +67,18 @@
     </p>
     <hr>
     <p>
-      Created by <a href="http://gabrielecirulli.com" target="_blank">Gabriele Cirulli.</a> Based on <a href="https://itunes.apple.com/us/app/1024!/id823499224" target="_blank">1024 by Veewo Studio.</a>
+    Created by <a href="http://gabrielecirulli.com" target="_blank">Gabriele Cirulli.</a> Based on <a href="https://itunes.apple.com/us/app/1024!/id823499224" target="_blank">1024 by Veewo Studio</a> and conceptually similar to <a href="http://asherv.com/threes/" target="_blank">Threes by Asher Vollmer.</a>
     </p>
   </div>
+
+  <script src="js/animframe_polyfill.js"></script>
+  <script src="js/hammer.min.js"></script>
+  <script src="js/keyboard_input_manager.js"></script>
+  <script src="js/html_actuator.js"></script>
+  <script src="js/grid.js"></script>
+  <script src="js/tile.js"></script>
+  <script src="js/local_score_manager.js"></script>
+  <script src="js/game_manager.js"></script>
+  <script src="js/application.js"></script>
 </body>
 </html>
diff --git a/js/animframe_polyfill.js b/js/animframe_polyfill.js
new file mode 100644
index 0000000000000000000000000000000000000000..c45a13e204478ffd468beebcb10bb143a283b34b
--- /dev/null
+++ b/js/animframe_polyfill.js
@@ -0,0 +1,26 @@
+(function() {
+  var lastTime = 0;
+  var vendors = ['webkit', 'moz'];
+  for(var x = 0; x < vendors.length && !window.requestAnimationFrame; ++x) {
+    window.requestAnimationFrame = window[vendors[x]+'RequestAnimationFrame'];
+    window.cancelAnimationFrame =
+    window[vendors[x]+'CancelAnimationFrame'] || window[vendors[x]+'CancelRequestAnimationFrame'];
+  }
+
+  if (!window.requestAnimationFrame) {
+    window.requestAnimationFrame = function(callback, element) {
+      var currTime = new Date().getTime();
+      var timeToCall = Math.max(0, 16 - (currTime - lastTime));
+      var id = window.setTimeout(function() { callback(currTime + timeToCall); },
+      timeToCall);
+      lastTime = currTime + timeToCall;
+      return id;
+    };
+  }
+
+  if (!window.cancelAnimationFrame) {
+    window.cancelAnimationFrame = function(id) {
+      clearTimeout(id);
+    };
+  }
+}());
diff --git a/js/application.js b/js/application.js
index 036ca3a2be6ade5598c7c86cfcdc4905ed5c6a31..a4d310a2579bf9940e3844e9e169d65b705865fe 100644
--- a/js/application.js
+++ b/js/application.js
@@ -1,6 +1,4 @@
-document.addEventListener("DOMContentLoaded", function () {
-  // Wait till the browser is ready to render the game (avoids glitches)
-  window.requestAnimationFrame(function () {
-    new GameManager(4, KeyboardInputManager, HTMLActuator, LocalScoreManager);
-  });
+// Wait till the browser is ready to render the game (avoids glitches)
+window.requestAnimationFrame(function () {
+  new GameManager(4, KeyboardInputManager, HTMLActuator, LocalScoreManager);
 });
diff --git a/js/keyboard_input_manager.js b/js/keyboard_input_manager.js
index 613360b8ba5318cf036b75bf029b5700ca93d561..d91e7f3b376106b93dd1cf0273d9451a59eb5efd 100644
--- a/js/keyboard_input_manager.js
+++ b/js/keyboard_input_manager.js
@@ -31,11 +31,15 @@ KeyboardInputManager.prototype.listen = function () {
     75: 0, // vim keybindings
     76: 1,
     74: 2,
-    72: 3
+    72: 3,
+    87: 0, // W
+    68: 1, // D
+    83: 2, // S
+    65: 3  // A
   };
 
   document.addEventListener("keydown", function (event) {
-    var modifiers = event.altKey && event.ctrlKey && event.metaKey &&
+    var modifiers = event.altKey || event.ctrlKey || event.metaKey ||
                     event.shiftKey;
     var mapped    = map[event.which];
 
diff --git a/style/helpers.scss b/style/helpers.scss
index 6bab89e8eb8dc65f5a799c29068c2fc1ce1297ba..a8f108c695aced23d16fbc14bd8e4e894d20e566 100644
--- a/style/helpers.scss
+++ b/style/helpers.scss
@@ -53,3 +53,10 @@
   -webkit-animation-fill-mode: #{$str};
   -moz-animation-fill-mode: #{$str};
 }
+
+// Media queries
+@mixin smaller($width) {
+  @media screen and (max-width: $width) {
+    @content;
+  }
+}
diff --git a/style/main.css b/style/main.css
index 784aeb5dabcc93e4cad30efb957e0865e0dd049c..07ed983cf8d6d0965364f744d86e70c1384098a6 100644
--- a/style/main.css
+++ b/style/main.css
@@ -140,6 +140,16 @@ hr {
   100% {
     opacity: 1; } }
 
+.game-container .game-message a {
+  display: inline-block;
+  background: #8f7a66;
+  border-radius: 3px;
+  padding: 0 20px;
+  text-decoration: none;
+  color: #f9f6f2;
+  height: 40px;
+  line-height: 42px; }
+
 .game-container {
   margin-top: 40px;
   position: relative;
@@ -179,14 +189,6 @@ hr {
       display: block;
       margin-top: 59px; }
     .game-container .game-message a {
-      display: inline-block;
-      background: #8f7a66;
-      border-radius: 3px;
-      padding: 0 20px;
-      text-decoration: none;
-      color: #f9f6f2;
-      height: 40px;
-      line-height: 42px;
       margin-left: 9px; }
     .game-container .game-message.game-won {
       background: rgba(237, 194, 46, 0.5);
@@ -222,20 +224,9 @@ hr {
   z-index: 2; }
 
 .tile {
-  background: red;
   width: 106.25px;
   height: 106.25px;
-  border-radius: 3px;
-  background: #eee4da;
-  text-align: center;
-  line-height: 116.25px;
-  font-size: 55px;
-  font-weight: bold;
-  z-index: 10;
-  -webkit-transition: 100ms ease-in-out;
-  -moz-transition: 100ms ease-in-out;
-  -webkit-transition-property: top, left;
-  -moz-transition-property: top, left; }
+  line-height: 116.25px; }
   .tile.tile-position-1-1 {
     position: absolute;
     left: 0px;
@@ -300,6 +291,18 @@ hr {
     position: absolute;
     left: 364px;
     top: 364px; }
+
+.tile {
+  border-radius: 3px;
+  background: #eee4da;
+  text-align: center;
+  font-weight: bold;
+  z-index: 10;
+  font-size: 55px;
+  -webkit-transition: 100ms ease-in-out;
+  -moz-transition: 100ms ease-in-out;
+  -webkit-transition-property: top, left;
+  -moz-transition-property: top, left; }
   .tile.tile-2 {
     background: #eee4da;
     box-shadow: 0 0 30px 10px rgba(243, 215, 116, 0), inset 0 0 0 1px rgba(255, 255, 255, 0); }
@@ -323,26 +326,41 @@ hr {
     background: #edcf72;
     box-shadow: 0 0 30px 10px rgba(243, 215, 116, 0.2381), inset 0 0 0 1px rgba(255, 255, 255, 0.14286);
     font-size: 45px; }
+    @media screen and (max-width: 480px) {
+      .tile.tile-128 {
+        font-size: 25px; } }
   .tile.tile-256 {
     color: #f9f6f2;
     background: #edcc61;
     box-shadow: 0 0 30px 10px rgba(243, 215, 116, 0.31746), inset 0 0 0 1px rgba(255, 255, 255, 0.19048);
     font-size: 45px; }
+    @media screen and (max-width: 480px) {
+      .tile.tile-256 {
+        font-size: 25px; } }
   .tile.tile-512 {
     color: #f9f6f2;
     background: #edc850;
     box-shadow: 0 0 30px 10px rgba(243, 215, 116, 0.39683), inset 0 0 0 1px rgba(255, 255, 255, 0.2381);
     font-size: 45px; }
+    @media screen and (max-width: 480px) {
+      .tile.tile-512 {
+        font-size: 25px; } }
   .tile.tile-1024 {
     color: #f9f6f2;
     background: #edc53f;
     box-shadow: 0 0 30px 10px rgba(243, 215, 116, 0.47619), inset 0 0 0 1px rgba(255, 255, 255, 0.28571);
     font-size: 35px; }
+    @media screen and (max-width: 480px) {
+      .tile.tile-1024 {
+        font-size: 15px; } }
   .tile.tile-2048 {
     color: #f9f6f2;
     background: #edc22e;
     box-shadow: 0 0 30px 10px rgba(243, 215, 116, 0.55556), inset 0 0 0 1px rgba(255, 255, 255, 0.33333);
     font-size: 35px; }
+    @media screen and (max-width: 480px) {
+      .tile.tile-2048 {
+        font-size: 15px; } }
 
 @-webkit-keyframes appear {
   0% {
@@ -434,3 +452,180 @@ hr {
 
 .game-explanation {
   margin-top: 50px; }
+
+@media screen and (max-width: 480px) {
+  html, body {
+    font-size: 15px; }
+
+  body {
+    margin: 20px 0;
+    padding: 0 20px; }
+
+  h1.title {
+    font-size: 50px; }
+
+  .container {
+    width: 280px;
+    margin: 0 auto; }
+
+  .score-container {
+    margin-top: 0; }
+
+  .heading {
+    margin-bottom: 10px; }
+
+  .game-container {
+    margin-top: 40px;
+    position: relative;
+    padding: 10px;
+    cursor: default;
+    -webkit-touch-callout: none;
+    -webkit-user-select: none;
+    -moz-user-select: none;
+    background: #bbada0;
+    border-radius: 6px;
+    width: 280px;
+    height: 280px;
+    -webkit-box-sizing: border-box;
+    -moz-box-sizing: border-box;
+    box-sizing: border-box; }
+    .game-container .game-message {
+      display: none;
+      position: absolute;
+      top: 0;
+      right: 0;
+      bottom: 0;
+      left: 0;
+      background: rgba(238, 228, 218, 0.5);
+      z-index: 100;
+      text-align: center;
+      -webkit-animation: fade-in 800ms ease 1200ms;
+      -moz-animation: fade-in 800ms ease 1200ms;
+      -webkit-animation-fill-mode: both;
+      -moz-animation-fill-mode: both; }
+      .game-container .game-message p {
+        font-size: 60px;
+        font-weight: bold;
+        height: 60px;
+        line-height: 60px;
+        margin-top: 222px; }
+      .game-container .game-message .lower {
+        display: block;
+        margin-top: 59px; }
+      .game-container .game-message a {
+        margin-left: 9px; }
+      .game-container .game-message.game-won {
+        background: rgba(237, 194, 46, 0.5);
+        color: #f9f6f2; }
+      .game-container .game-message.game-won, .game-container .game-message.game-over {
+        display: block; }
+
+  .grid-container {
+    position: absolute;
+    z-index: 1; }
+
+  .grid-row {
+    margin-bottom: 10px; }
+    .grid-row:last-child {
+      margin-bottom: 0; }
+    .grid-row:after {
+      content: "";
+      display: block;
+      clear: both; }
+
+  .grid-cell {
+    width: 57.5px;
+    height: 57.5px;
+    margin-right: 10px;
+    float: left;
+    border-radius: 3px;
+    background: rgba(238, 228, 218, 0.35); }
+    .grid-cell:last-child {
+      margin-right: 0; }
+
+  .tile-container {
+    position: absolute;
+    z-index: 2; }
+
+  .tile {
+    width: 57.5px;
+    height: 57.5px;
+    line-height: 67.5px; }
+    .tile.tile-position-1-1 {
+      position: absolute;
+      left: 0px;
+      top: 0px; }
+    .tile.tile-position-1-2 {
+      position: absolute;
+      left: 0px;
+      top: 68px; }
+    .tile.tile-position-1-3 {
+      position: absolute;
+      left: 0px;
+      top: 135px; }
+    .tile.tile-position-1-4 {
+      position: absolute;
+      left: 0px;
+      top: 203px; }
+    .tile.tile-position-2-1 {
+      position: absolute;
+      left: 68px;
+      top: 0px; }
+    .tile.tile-position-2-2 {
+      position: absolute;
+      left: 68px;
+      top: 68px; }
+    .tile.tile-position-2-3 {
+      position: absolute;
+      left: 68px;
+      top: 135px; }
+    .tile.tile-position-2-4 {
+      position: absolute;
+      left: 68px;
+      top: 203px; }
+    .tile.tile-position-3-1 {
+      position: absolute;
+      left: 135px;
+      top: 0px; }
+    .tile.tile-position-3-2 {
+      position: absolute;
+      left: 135px;
+      top: 68px; }
+    .tile.tile-position-3-3 {
+      position: absolute;
+      left: 135px;
+      top: 135px; }
+    .tile.tile-position-3-4 {
+      position: absolute;
+      left: 135px;
+      top: 203px; }
+    .tile.tile-position-4-1 {
+      position: absolute;
+      left: 203px;
+      top: 0px; }
+    .tile.tile-position-4-2 {
+      position: absolute;
+      left: 203px;
+      top: 68px; }
+    .tile.tile-position-4-3 {
+      position: absolute;
+      left: 203px;
+      top: 135px; }
+    .tile.tile-position-4-4 {
+      position: absolute;
+      left: 203px;
+      top: 203px; }
+
+  .game-container {
+    margin-top: 20px; }
+
+  .tile {
+    font-size: 35px; }
+
+  .game-message p {
+    font-size: 30px !important;
+    height: 30px !important;
+    line-height: 30px !important;
+    margin-top: 90px !important; }
+  .game-message .lower {
+    margin-top: 30px !important; } }
diff --git a/style/main.scss b/style/main.scss
index 96cdc7b1c353a001da69d47dd0cc58f66ba41609..4ffe138eee3e57ffb943994a629b4d74eaf99b5f 100644
--- a/style/main.scss
+++ b/style/main.scss
@@ -153,145 +153,159 @@ hr {
   }
 }
 
-.game-container {
-  margin-top: 40px;
-  position: relative;
-  padding: $grid-spacing;
-
-  cursor: default;
-  -webkit-touch-callout: none;
-  -webkit-user-select: none;
-  -moz-user-select: none;
+// Styles for buttons
+@mixin button {
+  display: inline-block;
+  background: darken($game-container-background, 20%);
+  border-radius: 3px;
+  padding: 0 20px;
+  text-decoration: none;
+  color: $bright-text-color;
+  height: 40px;
+  line-height: 42px;
+}
 
-  background: $game-container-background;
-  border-radius: $tile-border-radius * 2;
-  width: $field-width;
-  height: $field-width;
-  -webkit-box-sizing: border-box;
-  -moz-box-sizing: border-box;
-  box-sizing: border-box;
+// Game field mixin used to render CSS at different width
+@mixin game-field {
+  .game-container {
+    margin-top: 40px;
+    position: relative;
+    padding: $grid-spacing;
+
+    cursor: default;
+    -webkit-touch-callout: none;
+    -webkit-user-select: none;
+    -moz-user-select: none;
+
+    background: $game-container-background;
+    border-radius: $tile-border-radius * 2;
+    width: $field-width;
+    height: $field-width;
+    -webkit-box-sizing: border-box;
+    -moz-box-sizing: border-box;
+    box-sizing: border-box;
+
+    .game-message {
+      display: none;
+
+      position: absolute;
+      top: 0;
+      right: 0;
+      bottom: 0;
+      left: 0;
+      background: rgba($tile-color, .5);
+      z-index: 100;
+
+      text-align: center;
+
+      p {
+        font-size: 60px;
+        font-weight: bold;
+        height: 60px;
+        line-height: 60px;
+        margin-top: 222px;
+        // height: $field-width;
+        // line-height: $field-width;
+      }
 
-  .game-message {
-    display: none;
+      .lower {
+        display: block;
+        margin-top: 59px;
+      }
 
-    position: absolute;
-    top: 0;
-    right: 0;
-    bottom: 0;
-    left: 0;
-    background: rgba($tile-color, .5);
-    z-index: 100;
+      a {
+        @include button;
+        margin-left: 9px;
+        // margin-top: 59px;
+      }
 
-    text-align: center;
+      @include animation(fade-in 800ms ease $transition-speed * 12);
+      @include animation-fill-mode(both);
 
-    p {
-      font-size: 60px;
-      font-weight: bold;
-      height: 60px;
-      line-height: 60px;
-      margin-top: 222px;
-      // height: $field-width;
-      // line-height: $field-width;
-    }
+      &.game-won {
+        background: rgba($tile-gold-color, .5);
+        color: $bright-text-color;
+      }
 
-    .lower {
-      display: block;
-      margin-top: 59px;
+      &.game-won, &.game-over {
+        display: block;
+      }
     }
+  }
 
-    a {
-      display: inline-block;
-      background: darken($game-container-background, 20%);
-      border-radius: 3px;
-      padding: 0 20px;
-      text-decoration: none;
-      color: $bright-text-color;
-      height: 40px;
-      line-height: 42px;
-      margin-left: 9px;
-      // margin-top: 59px;
-    }
+  .grid-container {
+    position: absolute;
+    z-index: 1;
+  }
 
-    @include animation(fade-in 800ms ease $transition-speed * 12);
-    @include animation-fill-mode(both);
+  .grid-row {
+    margin-bottom: $grid-spacing;
 
-    &.game-won {
-      background: rgba($tile-gold-color, .5);
-      color: $bright-text-color;
+    &:last-child {
+      margin-bottom: 0;
     }
 
-    &.game-won, &.game-over {
+    &:after {
+      content: "";
       display: block;
+      clear: both;
     }
   }
-}
 
-.grid-container {
-  position: absolute;
-  z-index: 1;
-}
+  .grid-cell {
+    width: $tile-size;
+    height: $tile-size;
+    margin-right: $grid-spacing;
+    float: left;
 
-.grid-row {
-  margin-bottom: $grid-spacing;
+    border-radius: $tile-border-radius;
 
-  &:last-child {
-    margin-bottom: 0;
-  }
+    background: rgba($tile-color, .35);
 
-  &:after {
-    content: "";
-    display: block;
-    clear: both;
+    &:last-child {
+      margin-right: 0;
+    }
   }
-}
-
-.grid-cell {
-  width: $tile-size;
-  height: $tile-size;
-  margin-right: $grid-spacing;
-  float: left;
 
-  border-radius: $tile-border-radius;
-
-  background: rgba($tile-color, .35);
+  .tile-container {
+    position: absolute;
+    z-index: 2;
+  }
 
-  &:last-child {
-    margin-right: 0;
+  .tile {
+    width: $tile-size;
+    height: $tile-size;
+    line-height: $tile-size + 10px;
+
+    // Build position classes
+    @for $x from 1 through $grid-row-cells {
+      @for $y from 1 through $grid-row-cells {
+        &.tile-position-#{$x}-#{$y} {
+          position: absolute;
+          left: round(($tile-size + $grid-spacing) * ($x - 1));
+          top: round(($tile-size + $grid-spacing) * ($y - 1));
+        }
+      }
+    }
   }
 }
 
-.tile-container {
-  position: absolute;
-  z-index: 2;
-}
+// End of game-field mixin
+@include game-field;
 
 .tile {
-  background: red;
-  width: $tile-size;
-  height: $tile-size;
   border-radius: $tile-border-radius;
 
   background: $tile-color;
   text-align: center;
-  line-height: $tile-size + 10px;
-  font-size: 55px;
   font-weight: bold;
   z-index: 10;
 
+  font-size: 55px;
+
   @include transition($transition-speed ease-in-out);
   @include transition-property(top, left);
 
-  // Build position classes
-  @for $x from 1 through $grid-row-cells {
-    @for $y from 1 through $grid-row-cells {
-      &.tile-position-#{$x}-#{$y} {
-        position: absolute;
-        left: round(($tile-size + $grid-spacing) * ($x - 1));
-        top: round(($tile-size + $grid-spacing) * ($y - 1));
-      }
-    }
-  }
-
   $base: 2;
   $exponent: 1;
   $limit: 11;
@@ -345,8 +359,17 @@ hr {
       // Adjust font size for bigger numbers
       @if $power >= 100 and $power < 1000 {
         font-size: 45px;
+
+        // Media queries placed here to avoid carrying over the rest of the logic
+        @include smaller(480px) {
+          font-size: 25px;
+        }
       } @else if $power >= 1000 {
         font-size: 35px;
+
+        @include smaller(480px) {
+          font-size: 15px;
+        }
       }
     }
 
@@ -403,3 +426,63 @@ hr {
 .game-explanation {
   margin-top: 50px;
 }
+
+@include smaller(480px) {
+  // Redefine variables for smaller screens
+  $field-width: 280px;
+  $grid-spacing: 10px;
+  $grid-row-cells: 4;
+  $tile-size: ($field-width - $grid-spacing * ($grid-row-cells + 1)) / $grid-row-cells;
+  $tile-border-radius: 3px;
+
+  html, body {
+    font-size: 15px;
+  }
+
+  body {
+    margin: 20px 0;
+    padding: 0 20px;
+  }
+
+  h1.title {
+    font-size: 50px;
+  }
+
+  .container {
+    width: $field-width;
+    margin: 0 auto;
+  }
+
+  .score-container {
+    margin-top: 0;
+  }
+
+  .heading {
+    margin-bottom: 10px;
+  }
+
+  // Render the game field at the right width
+  @include game-field;
+
+  .game-container {
+    margin-top: 20px;
+  }
+
+  // Rest of the font-size adjustments in the tile class
+  .tile {
+    font-size: 35px;
+  }
+
+  .game-message {
+    p {
+      font-size: 30px !important;
+      height: 30px !important;
+      line-height: 30px !important;
+      margin-top: 90px !important;
+    }
+
+    .lower {
+      margin-top: 30px !important;
+    }
+  }
+}