diff --git a/include/android/sensor.h b/include/android/sensor.h
index 4683298..32c5c0a 100644
--- a/include/android/sensor.h
+++ b/include/android/sensor.h
@@ -114,15 +114,20 @@
     int32_t reserved0;
     int64_t timestamp;
     union {
-        float           data[16];
-        ASensorVector   vector;
-        ASensorVector   acceleration;
-        ASensorVector   magnetic;
-        float           temperature;
-        float           distance;
-        float           light;
-        float           pressure;
-        float           step_counter;
+        union {
+            float           data[16];
+            ASensorVector   vector;
+            ASensorVector   acceleration;
+            ASensorVector   magnetic;
+            float           temperature;
+            float           distance;
+            float           light;
+            float           pressure;
+        };
+        union {
+            uint64_t        data[8];
+            uint64_t        step_counter;
+        } u64;
     };
     int32_t reserved1[4];
 } ASensorEvent;
diff --git a/services/sensorservice/SensorDevice.cpp b/services/sensorservice/SensorDevice.cpp
index 16dabe8..18a1523 100644
--- a/services/sensorservice/SensorDevice.cpp
+++ b/services/sensorservice/SensorDevice.cpp
@@ -65,30 +65,26 @@
     }
 }
 
-void SensorDevice::dump(String8& result, char* buffer, size_t SIZE)
+void SensorDevice::dump(String8& result)
 {
     if (!mSensorModule) return;
     sensor_t const* list;
     ssize_t count = mSensorModule->get_sensors_list(mSensorModule, &list);
 
-    snprintf(buffer, SIZE, "%d h/w sensors:\n", int(count));
-    result.append(buffer);
+    result.appendFormat("%d h/w sensors:\n", int(count));
 
     Mutex::Autolock _l(mLock);
     for (size_t i=0 ; i<size_t(count) ; i++) {
         const Info& info = mActivationCount.valueFor(list[i].handle);
-        snprintf(buffer, SIZE, "handle=0x%08x, active-count=%d, rates(ms)={ ",
+        result.appendFormat("handle=0x%08x, active-count=%d, rates(ms)={ ",
                 list[i].handle,
                 info.rates.size());
-        result.append(buffer);
         for (size_t j=0 ; j<info.rates.size() ; j++) {
-            snprintf(buffer, SIZE, "%4.1f%s",
+            result.appendFormat("%4.1f%s",
                     info.rates.valueAt(j) / 1e6f,
                     j<info.rates.size()-1 ? ", " : "");
-            result.append(buffer);
         }
-        snprintf(buffer, SIZE, " }, selected=%4.1f ms\n",  info.delay / 1e6f);
-        result.append(buffer);
+        result.appendFormat(" }, selected=%4.1f ms\n",  info.delay / 1e6f);
     }
 }
 
diff --git a/services/sensorservice/SensorDevice.h b/services/sensorservice/SensorDevice.h
index c0b357d..ca67ce2 100644
--- a/services/sensorservice/SensorDevice.h
+++ b/services/sensorservice/SensorDevice.h
@@ -57,7 +57,7 @@
     status_t activate(void* ident, int handle, int enabled);
     status_t setDelay(void* ident, int handle, int64_t ns);
     status_t resetStateWithoutActuatingHardware(void *ident, int handle);
-    void dump(String8& result, char* buffer, size_t SIZE);
+    void dump(String8& result);
 };
 
 // ---------------------------------------------------------------------------
diff --git a/services/sensorservice/SensorFusion.cpp b/services/sensorservice/SensorFusion.cpp
index a0a17da..4014477 100644
--- a/services/sensorservice/SensorFusion.cpp
+++ b/services/sensorservice/SensorFusion.cpp
@@ -136,9 +136,9 @@
     return mAcc.getMinDelay();
 }
 
-void SensorFusion::dump(String8& result, char* buffer, size_t SIZE) {
+void SensorFusion::dump(String8& result) {
     const Fusion& fusion(mFusion);
-    snprintf(buffer, SIZE, "9-axis fusion %s (%d clients), gyro-rate=%7.2fHz, "
+    result.appendFormat("9-axis fusion %s (%d clients), gyro-rate=%7.2fHz, "
             "q=< %g, %g, %g, %g > (%g), "
             "b=< %g, %g, %g >\n",
             mEnabled ? "enabled" : "disabled",
@@ -152,7 +152,6 @@
             fusion.getBias().x,
             fusion.getBias().y,
             fusion.getBias().z);
-    result.append(buffer);
 }
 
 // ---------------------------------------------------------------------------
diff --git a/services/sensorservice/SensorFusion.h b/services/sensorservice/SensorFusion.h
index 3c2244e..432adbc 100644
--- a/services/sensorservice/SensorFusion.h
+++ b/services/sensorservice/SensorFusion.h
@@ -68,7 +68,7 @@
     float getPowerUsage() const;
     int32_t getMinDelay() const;
 
-    void dump(String8& result, char* buffer, size_t SIZE);
+    void dump(String8& result);
 };
 
 
diff --git a/services/sensorservice/SensorService.cpp b/services/sensorservice/SensorService.cpp
index 39e61b7..99993ba 100644
--- a/services/sensorservice/SensorService.cpp
+++ b/services/sensorservice/SensorService.cpp
@@ -187,47 +187,77 @@
 
 status_t SensorService::dump(int fd, const Vector<String16>& args)
 {
-    const size_t SIZE = 1024;
-    char buffer[SIZE];
     String8 result;
     if (!PermissionCache::checkCallingPermission(sDump)) {
-        snprintf(buffer, SIZE, "Permission Denial: "
+        result.appendFormat("Permission Denial: "
                 "can't dump SurfaceFlinger from pid=%d, uid=%d\n",
                 IPCThreadState::self()->getCallingPid(),
                 IPCThreadState::self()->getCallingUid());
-        result.append(buffer);
     } else {
         Mutex::Autolock _l(mLock);
-        snprintf(buffer, SIZE, "Sensor List:\n");
-        result.append(buffer);
+        result.append("Sensor List:\n");
         for (size_t i=0 ; i<mSensorList.size() ; i++) {
             const Sensor& s(mSensorList[i]);
             const sensors_event_t& e(mLastEventSeen.valueFor(s.getHandle()));
-            snprintf(buffer, SIZE,
-                    "%-48s| %-32s | 0x%08x | maxRate=%7.2fHz | "
-                    "last=<%5.1f,%5.1f,%5.1f>\n",
+            result.appendFormat(
+                    "%-48s| %-32s | 0x%08x | ",
                     s.getName().string(),
                     s.getVendor().string(),
-                    s.getHandle(),
-                    s.getMinDelay() ? (1000000.0f / s.getMinDelay()) : 0.0f,
-                    e.data[0], e.data[1], e.data[2]);
-            result.append(buffer);
-        }
-        SensorFusion::getInstance().dump(result, buffer, SIZE);
-        SensorDevice::getInstance().dump(result, buffer, SIZE);
+                    s.getHandle());
 
-        snprintf(buffer, SIZE, "%d active connections\n",
-                mActiveConnections.size());
-        result.append(buffer);
-        snprintf(buffer, SIZE, "Active sensors:\n");
-        result.append(buffer);
+            if (s.getMinDelay() > 0) {
+                result.appendFormat(
+                    "maxRate=%7.2fHz | ", 1e6f / s.getMinDelay());
+            } else {
+                result.append(s.getMinDelay() == 0
+                        ? "on-demand         | "
+                        : "one-shot          | ");
+            }
+
+            switch (s.getType()) {
+                case SENSOR_TYPE_ROTATION_VECTOR:
+                case SENSOR_TYPE_GEOMAGNETIC_ROTATION_VECTOR:
+                    result.appendFormat(
+                            "last=<%5.1f,%5.1f,%5.1f,%5.1f,%5.1f>\n",
+                            e.data[0], e.data[1], e.data[2], e.data[3], e.data[4]);
+                    break;
+                case SENSOR_TYPE_MAGNETIC_FIELD_UNCALIBRATED:
+                case SENSOR_TYPE_GYROSCOPE_UNCALIBRATED:
+                    result.appendFormat(
+                            "last=<%5.1f,%5.1f,%5.1f,%5.1f,%5.1f,%5.1f>\n",
+                            e.data[0], e.data[1], e.data[2], e.data[3], e.data[4], e.data[5]);
+                    break;
+                case SENSOR_TYPE_GAME_ROTATION_VECTOR:
+                    result.appendFormat(
+                            "last=<%5.1f,%5.1f,%5.1f,%5.1f>\n",
+                            e.data[0], e.data[1], e.data[2], e.data[3]);
+                    break;
+                case SENSOR_TYPE_SIGNIFICANT_MOTION:
+                case SENSOR_TYPE_STEP_DETECTOR:
+                    result.appendFormat( "last=<%f>\n", e.data[0]);
+                    break;
+                case SENSOR_TYPE_STEP_COUNTER:
+                    result.appendFormat( "last=<%llu>\n", e.u64.step_counter);
+                    break;
+                default:
+                    // default to 3 values
+                    result.appendFormat(
+                            "last=<%5.1f,%5.1f,%5.1f>\n",
+                            e.data[0], e.data[1], e.data[2]);
+                    break;
+            }
+        }
+        SensorFusion::getInstance().dump(result);
+        SensorDevice::getInstance().dump(result);
+
+        result.appendFormat("%d active connections\n", mActiveConnections.size());
+        result.append("Active sensors:\n");
         for (size_t i=0 ; i<mActiveSensors.size() ; i++) {
             int handle = mActiveSensors.keyAt(i);
-            snprintf(buffer, SIZE, "%s (handle=0x%08x, connections=%d)\n",
+            result.appendFormat("%s (handle=0x%08x, connections=%d)\n",
                     getSensorName(handle).string(),
                     handle,
                     mActiveSensors.valueAt(i)->getNumConnections());
-            result.append(buffer);
         }
     }
     write(fd, result.string(), result.size());