diff --git a/apps/compass.js b/apps/compass.js
index c1d131093..10895e3cd 100644
--- a/apps/compass.js
+++ b/apps/compass.js
@@ -23,7 +23,7 @@ Bangle.on('mag', function(m) {
   g.fillRect(70,0,170,24);
   g.setColor(0xffff);
   g.setFontAlign(0,0);
-  g.drawString((m.heading===undefined)?"---":Math.round(m.heading),120,12);
+  g.drawString(isNaN(m.heading)?"---":Math.round(m.heading),120,12);
   g.setColor(0,0,0);
   arrow(oldHeading,0);
   arrow(oldHeading+180,0);
diff --git a/apps/heartrate.js b/apps/heartrate.js
index c31314af1..84658e85f 100644
--- a/apps/heartrate.js
+++ b/apps/heartrate.js
@@ -14,9 +14,9 @@ function readHRM() {
   min=Math.min(min*0.97+a*0.03,a);
   max=Math.max(max*0.97+a*0.03,a);
   y = E.clip(170 - (a*960*4),100,230);
-  if (x==0) { 
-    g.clearRect(0,100,239,239); 
-    g.moveTo(-100,0); 
+  if (x==0) {
+    g.clearRect(0,100,239,239);
+    g.moveTo(-100,0);
   }
   /*g.setColor(0,1,0);
   var z = 170 - (min*960*4); g.fillRect(x,z,x,z);
@@ -39,11 +39,16 @@ function readHRM() {
           t.sort();
           // average the middle 3
           var mid = t.length>>1;
-          hrm = (t[mid]+t[mid+1]+t[mid+2])/3;
+          if (mid+2<t.length)
+            hrm = (t[mid]+t[mid+1]+t[mid+2])/3;
+          else if (mid<t.length)
+            hrm = t[mid];
+          else
+            hrm = 0;
           g.setFontVector(40);
           g.setFontAlign(0,0);
           g.clearRect(0,0,239,100);
-          var str = Math.round(hrm);
+          var str = hrm ? Math.round(hrm) : "?";
           var px = 120;
           g.drawString(str,px,40);
           px += g.stringWidth(str)/2;
diff --git a/apps/hid-binary-keyboard-icon.js b/apps/hid-binary-keyboard-icon.js
new file mode 100644
index 000000000..ca63665de
--- /dev/null
+++ b/apps/hid-binary-keyboard-icon.js
@@ -0,0 +1 @@
+require("heatshrink").decompress(atob("mEwwhC/AH4A/AHeIDC+AC60IC/51ELoIXTCYMIDISLpC/67dxAAJHBYsLhAYKLhgXXHhWAdoQbBApAvhBgYcCAogXkI64XYhDtII/oMUERTyDABJ0FPI4A/AH4A/AGY="))
diff --git a/apps/hid-binary-keyboard.js b/apps/hid-binary-keyboard.js
new file mode 100644
index 000000000..6c595ff8e
--- /dev/null
+++ b/apps/hid-binary-keyboard.js
@@ -0,0 +1,117 @@
+/*
+Binary search keyboard for typing with
+the touchscreen
+*/
+
+var storage = require('Storage');
+
+const settings = storage.readJSON('@setting') || { HID: false };
+const KEY = {
+  A           : 4 ,
+  B           : 5 ,
+  C           : 6 ,
+  D           : 7 ,
+  E           : 8 ,
+  F           : 9 ,
+  G           : 10,
+  H           : 11,
+  I           : 12,
+  J           : 13,
+  K           : 14,
+  L           : 15,
+  M           : 16,
+  N           : 17,
+  O           : 18,
+  P           : 19,
+  Q           : 20,
+  R           : 21,
+  S           : 22,
+  T           : 23,
+  U           : 24,
+  V           : 25,
+  W           : 26,
+  X           : 27,
+  Y           : 28,
+  Z           : 29,
+  1           : 30,
+  2           : 31,
+  3           : 32,
+  4           : 33,
+  5           : 34,
+  6           : 35,
+  7           : 36,
+  8           : 37,
+  9           : 38,
+  0           : 39
+};
+
+function sendHID(code) {
+  return new Promise(resolve=>{
+    NRF.sendHIDReport([2,0,0,code,0,0,0,0,0], () => {
+      NRF.sendHIDReport([2,0,0,0,0,0,0,0,0], resolve);
+    });
+  });
+};
+
+function showChars(x,chars) {
+  var lines = Math.round(Math.sqrt(chars.length)*2);
+  g.setFontAlign(0,0);
+  var sy = Math.round(200/lines);
+  var sx = sy;
+  g.setFont("Vector", sy-2);
+  var y = (240 - lines*sy);
+  var last = 0;
+  for (var i=0;i<lines;i++) {
+    var n = Math.round(chars.length*(i+1)/lines);
+    var xo = x + (120 - sx*(n-last-1))/2;
+    for (var j=last;j<n;j++)
+      g.drawString(chars[j], xo + (j-last)*sx, y + sy*i)
+    last = n;
+  }
+}
+
+function show(chars,callback) {
+  g.clear();
+  if (chars.length==1) {
+    callback(chars);
+    return;
+  }
+  var m = chars.length/2;
+  charl=chars.slice(0,m);
+  charr=chars.slice(m);
+  showChars(0,charl);
+  showChars(120,charr);
+  setWatch(() => {
+    clearWatch();
+    show(charl,callback);
+  }, BTN4);
+  setWatch(() => {
+    clearWatch();
+    show(charr,callback);
+  }, BTN5);
+}
+
+function getCharacter() {
+  return new Promise(resolve => {
+    show("ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789",resolve);
+  });
+}
+
+function startKeyboardHID() {
+  getCharacter().then(ch => {
+    return sendHID(KEY[ch]);
+  }).then(startKeyboardHID);
+};
+
+if (!settings.HID) {
+  E.showMessage('HID disabled');
+  setTimeout(load, 1000);
+} else {
+  startKeyboardHID();
+  setWatch(() => {
+    sendHID(44); // space
+  }, BTN2, {repeat:true});
+  setWatch(() => {
+    sendHID(40); // enter
+  }, BTN3, {repeat:true});
+}
diff --git a/apps/hid-binary-keyboard.json b/apps/hid-binary-keyboard.json
new file mode 100644
index 000000000..e2059a9c2
--- /dev/null
+++ b/apps/hid-binary-keyboard.json
@@ -0,0 +1,5 @@
+{
+  "name": "Binary Keyboard","type":"app",
+  "icon": "*hidbkbd",
+  "src": "-hidbkbd"
+}
diff --git a/apps/hid-binary-keyboard.png b/apps/hid-binary-keyboard.png
new file mode 100644
index 000000000..19aec3c05
Binary files /dev/null and b/apps/hid-binary-keyboard.png differ
diff --git a/testing/binary-keyboard.js b/testing/binary-keyboard.js
deleted file mode 100644
index 3b68179a4..000000000
--- a/testing/binary-keyboard.js
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
-Binary search keyboard for typing with
-the touchscreen
-*/
-
-function showChars(x,chars) {
-  var lines = Math.round(Math.sqrt(chars.length)*2);
-  g.setFontAlign(0,0);
-  var sy = Math.round(200/lines);
-  var sx = sy;
-  g.setFont("Vector", sy-2);
-  var y = (240 - lines*sy);
-  var last = 0;
-  for (var i=0;i<lines;i++) {
-    var n = Math.round(chars.length*(i+1)/lines);
-    var xo = x + (120 - sx*(n-last-1))/2;
-    for (var j=last;j<n;j++)
-      g.drawString(chars[j], xo + (j-last)*sx, y + sy*i)
-    last = n;
-  }
-}
-
-function show(chars,callback) {
-  g.clear();
-  if (chars.length==1) {
-    callback(chars);
-    return;
-  }
-  var m = chars.length/2;
-  charl=chars.slice(0,m);
-  charr=chars.slice(m);
-  showChars(0,charl);
-  showChars(120,charr);
-  setWatch(() => {
-    clearWatch();
-    show(charl,callback);
-  }, BTN4);
-  setWatch(() => {
-    clearWatch();
-    show(charr,callback);
-  }, BTN5);
-}
-
-function getCharacter() {
-  return new Promise(resolve => {
-    show("ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789",resolve);
-  });
-}
-
-getCharacter().then(print)
\ No newline at end of file