diff --git a/apps/hrrawexp/app.js b/apps/hrrawexp/app.js
new file mode 100644
index 000000000..f78d3fbf6
--- /dev/null
+++ b/apps/hrrawexp/app.js
@@ -0,0 +1,97 @@
+var counter = 1;
+var logging_started;
+var interval;
+var value;
+
+var file = require("Storage").open("hrm_log.csv", "w");
+file.write("");
+
+file = require("Storage").open("hrm_log.csv", "a");
+
+function update_timer() {
+    g.clear();
+    g.setColor("#00ff7f");
+    g.setFont("6x8", 4);
+    g.setFontAlign(0, 0); // center font
+
+    g.drawString(counter, 120, 120);
+    g.setFont("6x8", 2);
+    g.setFontAlign(-1, -1);
+    g.drawString("-", 220, 200);
+    g.drawString("+", 220, 40);
+    g.drawString("GO", 210, 120);
+
+    g.setColor("#ffffff");
+    g.setFontAlign(0, 0); // center font
+    g.drawString("Timer (minutes)", 120, 90);
+
+    g.setFont("6x8", 4); // bitmap font, 8x magnified
+
+    if (!logging_started)
+        g.flip();
+}
+
+function btn1Pressed() {
+    if (!logging_started) {
+        if (counter < 60)
+            counter += 1;
+        else
+            counter = 1;
+        update_timer();
+    }
+}
+
+function btn3Pressed() {
+    if (!logging_started) {
+        if (counter > 1)
+            counter -= 1;
+        else
+            counter = 60;
+        update_timer();
+    }
+}
+
+function btn2Pressed() {
+    launchtime = 0 | getTime();
+    file.write(launchtime + "," + "\n");
+    logging_started = true;
+    counter = counter * 60;
+    interval = setInterval(countDown, 1000);
+    Bangle.setHRMPower(1);
+}
+
+function fmtMSS(e) {
+    var m = Math.floor(e % 3600 / 60).toString().padStart(2, '0'),
+        s = Math.floor(e % 60).toString().padStart(2, '0');
+    return m + ':' + s;
+}
+
+function countDown() {
+    g.clear();
+    counter--;
+    if (counter == 0) {
+        Bangle.setHRMPower(0);
+        clearInterval(interval);
+        g.drawString("Finished", g.getWidth() / 2, g.getHeight() / 2);
+        Bangle.buzz(500, 1);
+    }
+    else
+        g.drawString(fmtMSS(counter), g.getWidth() / 2, g.getHeight() / 2);
+}
+
+update_timer();
+
+setWatch(btn1Pressed, BTN1, { repeat: true });
+setWatch(btn2Pressed, BTN2, { repeat: true });
+setWatch(btn3Pressed, BTN3, { repeat: true });
+
+Bangle.on('HRM', function (hrm) {
+    for (let i = 0; i < hrm.raw.length; i++) {
+        value = hrm.raw[i];
+        if (value < -2)
+            value = -2;
+        if (value > 6)
+            value = 6;
+        file.write(value + "," + "\n");
+    }
+});