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diff --git a/android/WALT/app/src/main/java/org/chromium/latency/walt/RemoteClockInfo.java b/android/WALT/app/src/main/java/org/chromium/latency/walt/RemoteClockInfo.java
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+++ b/android/WALT/app/src/main/java/org/chromium/latency/walt/RemoteClockInfo.java
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+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.chromium.latency.walt;
+
+import android.util.Log;
+
+import java.lang.reflect.Method;
+
+/**
+ * Representation of our best knowledge of the remote clock.
+ * All time variables here are stored in microseconds.
+ *
+ * Which time reporting function is used locally on Android:
+ * This app uses SystemClock.uptimeMillis() for keeping local time which, up to
+ * units, is the same time reported by System.nanoTime() and by
+ * clock_gettime(CLOCK_MONOTONIC, &ts) from time.h and is, roughly, the time
+ * elapsed since last boot, excluding sleep time.
+ *
+ * base_time is the local Android time when remote clock was zeroed.
+ *
+ * micros() is our best available approximation of the current reading of the remote clock.
+ *
+ * Immediately after synchronization minLag is set to zero and the remote clock guaranteed to lag
+ * behind what micros() reports by at most maxLag.
+ *
+ * Immediately after synchronization or an update of the bounds (minLag, maxLag) the following holds
+ * t_remote + minLag < micros() < t_rmote + maxLag
+ *
+ * For more details about clock synchronization refer to
+ * https://github.com/google/walt/blob/master/android/WALT/app/src/main/jni/README.md
+ * and sync_clock.c
+ */
+
+public class RemoteClockInfo {
+    public int minLag;
+    public int maxLag;
+    public long baseTime;
+
+
+    public long micros() {
+        return microTime() - baseTime;
+    }
+
+    public static long microTime() {
+        return System.nanoTime() / 1000;
+    }
+
+
+    /**
+     Find the wall time when uptime was zero = CLOCK_REALTIME - CLOCK_MONOTONIC
+
+     Needed for TCP bridge because Python prior to 3.3 has no direct access to CLOCK_MONOTONIC
+     so the bridge returns timestamps as wall time and we need to convert them to CLOCK_MONOTONIC.
+
+     See:
+     [1] https://docs.python.org/3/library/time.html#time.CLOCK_MONOTONIC
+     [2] http://stackoverflow.com/questions/14270300/what-is-the-difference-between-clock-monotonic-clock-monotonic-raw
+     [3] http://stackoverflow.com/questions/1205722/how-do-i-get-monotonic-time-durations-in-python
+
+     android.os.SystemClock.currentTimeMicros() is hidden by @hide which means it can't be called
+     directly - calling it via reflection.
+
+     See:
+     http://stackoverflow.com/questions/17035271/what-does-hide-mean-in-the-android-source-code
+     */
+    public static long uptimeZero() {
+        long t = -1;
+        long dt = Long.MAX_VALUE;
+        try {
+            Class cls = Class.forName("android.os.SystemClock");
+            Method myTimeGetter = cls.getMethod("currentTimeMicro");
+            t = (long) myTimeGetter.invoke(null);
+            dt = t - microTime();
+        } catch (Exception e) {
+            Log.i("WALT.uptimeZero", e.getMessage());
+        }
+
+        return dt;
+    }
+
+    public static long currentTimeMicro() {
+
+        long t = -1;
+        try {
+            Class cls = Class.forName("android.os.SystemClock");
+            Method myTimeGetter = cls.getMethod("currentTimeMicro");
+            t = (long) myTimeGetter.invoke(null);
+        } catch (Exception e) {
+            Log.i("WALT.currentTimeMicro", e.getMessage());
+        }
+
+        return t;
+    }
+
+    public int getMeanLag() {
+        return (minLag + maxLag) / 2;
+    }
+
+    public String toString(){
+        return "Remote clock [us]: current time = " + micros() + " baseTime = " + baseTime +
+                " lagBounds = (" + minLag + ", " + maxLag + ")";
+    }
+}