diff --git a/app/src/main/java/net/voussoir/trkpt/TrackFragment.kt b/app/src/main/java/net/voussoir/trkpt/TrackFragment.kt
index 8897f11..0e42f91 100644
--- a/app/src/main/java/net/voussoir/trkpt/TrackFragment.kt
+++ b/app/src/main/java/net/voussoir/trkpt/TrackFragment.kt
@@ -86,6 +86,8 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
     lateinit var use_trkpt_as_end_button: ImageButton
     lateinit var isolate_trkseg_button: ImageButton
     lateinit var when_was_i_here_button: ImageButton
+    lateinit var interpolate_points_button: ImageButton
+    var ready_to_interpolate: Boolean = false
     var track_query_start_time_previous: Int = 0
     var track_query_end_time_previous: Int = 0
     private lateinit var mapView: MapView
@@ -342,6 +344,20 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
             render_track()
         }
 
+        interpolate_points_button = rootView.findViewById(R.id.interpolate_points_button)
+        interpolate_points_button.setOnClickListener {
+            Log.i("VOUSSOIR", "interpolate_points_button.")
+            if (ready_to_interpolate)
+            {
+                interpolate_points_button.setColorFilter(null)
+            }
+            else
+            {
+                interpolate_points_button.setColorFilter(resources.getColor(R.color.fuchsia))
+            }
+            ready_to_interpolate = !ready_to_interpolate
+        }
+
         save_track_button.setOnClickListener {
             val dialog = Dialog(activity as Context)
             dialog.setContentView(R.layout.dialog_rename_track)
@@ -433,7 +449,10 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
             mapView.overlays.remove(selected_trkpt_marker)
             mapView.invalidate()
         }
+        ready_to_interpolate = false
+        interpolate_points_button.setColorFilter(null)
         delete_selected_trkpt_button.visibility = View.GONE
+        interpolate_points_button.visibility = View.GONE
         use_trkpt_as_start_button.visibility = View.GONE
         use_trkpt_as_end_button.visibility = View.GONE
         isolate_trkseg_button.visibility = View.GONE
@@ -527,6 +546,20 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
                 }
                 val trkpt = (points[point]) as Trkpt
                 Log.i("VOUSSOIR", "Clicked ${trkpt.device_id} ${trkpt.time}")
+                if (ready_to_interpolate)
+                {
+                    val mid_location = Location("interpolated")
+                    mid_location.latitude = (selected_trkpt!!.latitude + trkpt.latitude) / 2
+                    mid_location.longitude = (selected_trkpt!!.longitude + trkpt.longitude) / 2
+                    mid_location.altitude = (selected_trkpt!!.altitude + trkpt.altitude) / 2
+                    mid_location.time = (selected_trkpt!!.time + trkpt.time) / 2
+                    mid_location.accuracy = 0f
+                    val mid_trkpt = Trkpt(trkpt.device_id, mid_location)
+                    deselect_trkpt()
+                    trackbook.database.insert_trkpt(mid_trkpt, commit=true)
+                    handler.post(requery_and_render)
+                    return
+                }
                 selected_trkpt = trkpt
                 selected_trkpt_info.text = "${trkpt.time}\n${iso8601_local(trkpt.time)}\n${trkpt.latitude}\n${trkpt.longitude}\n${trkpt.accuracy}"
                 selected_trkpt_marker.position = trkpt
@@ -534,6 +567,7 @@ class TrackFragment : Fragment(), MapListener, YesNoDialog.YesNoDialogListener
                 {
                     mapView.overlays.add(selected_trkpt_marker)
                 }
+                interpolate_points_button.visibility = View.VISIBLE
                 delete_selected_trkpt_button.visibility = View.VISIBLE
                 use_trkpt_as_start_button.visibility = View.VISIBLE
                 use_trkpt_as_end_button.visibility = View.VISIBLE
diff --git a/app/src/main/res/drawable/ic_interpolate_24dp.xml b/app/src/main/res/drawable/ic_interpolate_24dp.xml
new file mode 100644
index 0000000..aa12297
--- /dev/null
+++ b/app/src/main/res/drawable/ic_interpolate_24dp.xml
@@ -0,0 +1,12 @@
+<vector
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    android:name="vector"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <path
+        android:name="path_1"
+        android:pathData="M 11.059 4.479 L 11.059 6.958 L 8.578 6.958 L 8.578 8.958 L 11.059 8.958 L 11.059 11.438 L 13.059 11.438 L 13.059 8.958 L 15.539 8.958 L 15.539 6.958 L 13.059 6.958 L 13.059 4.479 Z M 12 13.385 C 11.07 13.385 10.268 13.938 9.891 14.729 L 1.76 14.729 L 1.76 16.729 L 9.891 16.729 C 10.268 17.519 11.07 18.072 12 18.072 C 12.93 18.072 13.731 17.519 14.109 16.729 L 22.357 16.729 L 22.357 14.729 L 14.109 14.729 C 13.731 13.938 12.93 13.385 12 13.385 Z"
+        android:fillColor="@color/icon_default" />
+</vector>
diff --git a/app/src/main/res/layout/fragment_track.xml b/app/src/main/res/layout/fragment_track.xml
index b063e1c..baec6c5 100755
--- a/app/src/main/res/layout/fragment_track.xml
+++ b/app/src/main/res/layout/fragment_track.xml
@@ -91,8 +91,8 @@
                 android:src="@drawable/ic_end_here_24dp"
                 android:visibility="gone"
                 app:backgroundTint="@color/default_transparent"
-                app:layout_constraintTop_toBottomOf="@+id/when_was_i_here_button"
-                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintTop_toTopOf="@+id/when_was_i_here_button"
+                app:layout_constraintEnd_toStartOf="@+id/when_was_i_here_button"
                 app:srcCompat="@drawable/ic_end_here_24dp" />
 
             <ImageButton
@@ -116,10 +116,23 @@
                 android:tooltipText="Isolate track segment"
                 android:visibility="gone"
                 app:backgroundTint="@color/default_transparent"
-                app:layout_constraintBottom_toBottomOf="parent"
-                app:layout_constraintEnd_toStartOf="@+id/delete_selected_trkpt_button"
+                app:layout_constraintTop_toBottomOf="@+id/when_was_i_here_button"
+                app:layout_constraintEnd_toEndOf="@+id/when_was_i_here_button"
                 app:srcCompat="@drawable/ic_timeline_24dp" />
 
+            <ImageButton
+                android:id="@+id/interpolate_points_button"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:contentDescription="Interpolate between two points"
+                android:tooltipText="Interpolate between two points"
+                android:src="@drawable/ic_interpolate_24dp"
+                android:visibility="gone"
+                app:backgroundTint="@color/default_transparent"
+                app:layout_constraintTop_toTopOf="@+id/isolate_trkseg_button"
+                app:layout_constraintEnd_toStartOf="@+id/isolate_trkseg_button"
+                app:srcCompat="@drawable/ic_bug_report_24dp" />
+
             <ImageButton
                 android:id="@+id/delete_selected_trkpt_button"
                 android:layout_width="wrap_content"