diff --git a/mobile/android/base/gfx/DisplayPortCalculator.java b/mobile/android/base/gfx/DisplayPortCalculator.java
index a46ed5cf37da..3f56c2a3666f 100644
--- a/mobile/android/base/gfx/DisplayPortCalculator.java
+++ b/mobile/android/base/gfx/DisplayPortCalculator.java
@@ -13,7 +13,6 @@ import org.json.JSONArray;
 
 import android.graphics.PointF;
 import android.graphics.RectF;
-import android.util.FloatMath;
 import android.util.Log;
 
 import java.util.HashMap;
@@ -184,10 +183,10 @@ final class DisplayPortCalculator {
         float top = metrics.viewportRectTop - margins.top;
         float right = metrics.viewportRectRight + margins.right;
         float bottom = metrics.viewportRectBottom + margins.bottom;
-        left = Math.max(metrics.pageRectLeft, TILE_SIZE * FloatMath.floor(left / TILE_SIZE));
-        top = Math.max(metrics.pageRectTop, TILE_SIZE * FloatMath.floor(top / TILE_SIZE));
-        right = Math.min(metrics.pageRectRight, TILE_SIZE * FloatMath.ceil(right / TILE_SIZE));
-        bottom = Math.min(metrics.pageRectBottom, TILE_SIZE * FloatMath.ceil(bottom / TILE_SIZE));
+        left = (float) Math.max(metrics.pageRectLeft, TILE_SIZE * Math.floor(left / TILE_SIZE));
+        top = (float) Math.max(metrics.pageRectTop, TILE_SIZE * Math.floor(top / TILE_SIZE));
+        right = (float) Math.min(metrics.pageRectRight, TILE_SIZE * Math.ceil(right / TILE_SIZE));
+        bottom = (float) Math.min(metrics.pageRectBottom, TILE_SIZE * Math.ceil(bottom / TILE_SIZE));
         return new DisplayPortMetrics(left, top, right, bottom, zoom);
     }
 
@@ -747,7 +746,7 @@ final class DisplayPortCalculator {
         public boolean drawTimeUpdate(long millis, int pixels) {
             // calculate the number of frames it took to draw a viewport-sized area
             float normalizedTime = (float)mPixelArea * millis / pixels;
-            int normalizedFrames = (int)FloatMath.ceil(normalizedTime * 60f / 1000f);
+            int normalizedFrames = (int) Math.ceil(normalizedTime * 60f / 1000f);
             // broaden our range on how long it takes to draw if the draw falls outside
             // the range. this allows it to grow gradually. this heuristic may need to
             // be tweaked into more of a floating window average or something.
diff --git a/mobile/android/base/gfx/IntSize.java b/mobile/android/base/gfx/IntSize.java
index b758d732c2ed..0e847158d70b 100644
--- a/mobile/android/base/gfx/IntSize.java
+++ b/mobile/android/base/gfx/IntSize.java
@@ -8,8 +8,6 @@ package org.mozilla.gecko.gfx;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import android.util.FloatMath;
-
 public class IntSize {
     public final int width, height;
 
@@ -75,7 +73,7 @@ public class IntSize {
     }
 
     public static int largestPowerOfTwoLessThan(float value) {
-        int val = (int)FloatMath.floor(value);
+        int val = (int) Math.floor(value);
         if (val <= 0) {
             throw new IllegalArgumentException("Error: value must be > 0");
         }
diff --git a/mobile/android/base/gfx/JavaPanZoomController.java b/mobile/android/base/gfx/JavaPanZoomController.java
index d27eef807231..42b7c65ffed6 100644
--- a/mobile/android/base/gfx/JavaPanZoomController.java
+++ b/mobile/android/base/gfx/JavaPanZoomController.java
@@ -21,7 +21,6 @@ import org.mozilla.gecko.util.ThreadUtils;
 
 import android.graphics.PointF;
 import android.graphics.RectF;
-import android.util.FloatMath;
 import android.util.Log;
 import android.view.GestureDetector;
 import android.view.InputDevice;
@@ -668,7 +667,7 @@ class JavaPanZoomController
     private float panDistance(MotionEvent move) {
         float dx = mX.panDistance(move.getX(0));
         float dy = mY.panDistance(move.getY(0));
-        return FloatMath.sqrt(dx * dx + dy * dy);
+        return (float) Math.sqrt(dx * dx + dy * dy);
     }
 
     private void track(float x, float y, long time) {
@@ -801,7 +800,7 @@ class JavaPanZoomController
     private float getVelocity() {
         float xvel = mX.getRealVelocity();
         float yvel = mY.getRealVelocity();
-        return FloatMath.sqrt(xvel * xvel + yvel * yvel);
+        return (float) Math.sqrt(xvel * xvel + yvel * yvel);
     }
 
     @Override
diff --git a/mobile/android/tests/browser/robocop/MotionEventHelper.java b/mobile/android/tests/browser/robocop/MotionEventHelper.java
index 0f1402acf14c..ce1c5d1ed795 100644
--- a/mobile/android/tests/browser/robocop/MotionEventHelper.java
+++ b/mobile/android/tests/browser/robocop/MotionEventHelper.java
@@ -9,7 +9,6 @@ import org.mozilla.gecko.gfx.LayerView;
 
 import android.app.Instrumentation;
 import android.os.SystemClock;
-import android.util.FloatMath;
 import android.util.Log;
 import android.view.MotionEvent;
 
@@ -133,7 +132,7 @@ class MotionEventHelper {
         // will trigger the fling.
         final float dx = (endX - startX) / 2;
         final float dy = (endY - startY) / 2;
-        float distance = FloatMath.sqrt((dx * dx) + (dy * dy));
+        float distance = (float) Math.sqrt((dx * dx) + (dy * dy));
         final long time = (long)(distance / velocity);
         if (time <= 0) {
             throw new IllegalArgumentException( "Fling parameters require too small a time period" );