diff --git a/apps.json b/apps.json
index f0f186869..b7d3fb8e0 100644
--- a/apps.json
+++ b/apps.json
@@ -1214,5 +1214,17 @@
       {"name":"bledetect.app.js","url":"bledetect.js"},
       {"name":"bledetect.img","url":"bledetect-icon.js","evaluate":true}
     ]
+  },
+    { "id": "calculator",
+    "name": "Calculator",
+    "shortName":"Calculator",
+    "icon": "calculator.png",
+    "version":"0.01",
+    "description": "Basic calculator reminiscent of MacOs's one. Handy for small calculus. Push button1 and 3 to navigate up/down, tap right or left to navigate the sides, push button 2 to select.",
+    "tags": "app,tool",
+    "storage": [
+      {"name":"calculator.app.js","url":"app.js"},
+      {"name":"calculator.img","url":"calculator-icon.js","evaluate":true}
+    ]
   }
 ]
diff --git a/apps/calculator/ChangeLog b/apps/calculator/ChangeLog
new file mode 100644
index 000000000..5560f00bc
--- /dev/null
+++ b/apps/calculator/ChangeLog
@@ -0,0 +1 @@
+0.01: New App!
diff --git a/apps/calculator/app.js b/apps/calculator/app.js
new file mode 100644
index 000000000..91dd7c49d
--- /dev/null
+++ b/apps/calculator/app.js
@@ -0,0 +1,352 @@
+/**
+ * BangleJS Calculator
+ *
+ * Original Author: Frederic Rousseau https://github.com/fredericrous
+ * Created: April 2020
+ */
+
+g.clear();
+Graphics.prototype.setFont7x11Numeric7Seg = function() {
+  this.setFontCustom(atob("ACAB70AYAwBgC94AAAAAAAAAAB7wAAPQhhDCGELwAAAAhDCGEMIXvAAeACAEAIAQPeAA8CEMIYQwhA8AB70IYQwhhCB4AAAIAQAgBAB7wAHvQhhDCGEL3gAPAhDCGEMIXvAAe9CCEEIIQPeAA94EIIQQghA8AB70AYAwBgCAAAAHgQghBCCF7wAHvQhhDCGEIAAAPehBCCEEIAAAAA=="), 46, atob("AgAHBwcHBwcHBwcHAAAAAAAAAAcHBwcHBw=="), 11);
+};
+
+var DEFAULT_SELECTION = '5';
+var BOTTOM_MARGIN = 10;
+var RIGHT_MARGIN = 20;
+var COLORS = {
+  // [normal, selected]
+  DEFAULT: ['#7F8183', '#A6A6A7'],
+  OPERATOR: ['#F99D1C', '#CA7F2A'],
+  SPECIAL: ['#65686C', '#7F8183']
+};
+
+var keys = {
+  '0': {
+    xy: [0, 200, 120, 240],
+    trbl: '2.00'
+  },
+  '.': {
+    xy: [120, 200, 180, 240],
+    trbl: '3=.0'
+  },
+  '=': {
+    xy: [181, 200, 240, 240],
+    trbl: '+==.',
+    color: COLORS.OPERATOR
+  },
+  '1': {
+    xy: [0, 160, 60, 200],
+    trbl: '4201'
+  },
+  '2': {
+    xy: [60, 160, 120, 200],
+    trbl: '5301'
+  },
+  '3': {
+    xy: [120, 160, 180, 200],
+    trbl: '6+.2'
+  },
+  '+': {
+    xy: [181, 160, 240, 200],
+    trbl: '-+=3',
+    color: COLORS.OPERATOR
+  },
+  '4': {
+    xy: [0, 120, 60, 160],
+    trbl: '7514'
+  },
+  '5': {
+    xy: [60, 120, 120, 160],
+    trbl: '8624'
+  },
+  '6': {
+    xy: [120, 120, 180, 160],
+    trbl: '9-35'
+  },
+  '-': {
+    xy: [181, 120, 240, 160],
+    trbl: '*-+6',
+    color: COLORS.OPERATOR
+  },
+  '7': {
+    xy: [0, 80, 60, 120],
+    trbl: 'R847'
+  },
+  '8': {
+    xy: [60, 80, 120, 120],
+    trbl: 'N957'
+  },
+  '9': {
+    xy: [120, 80, 180, 120],
+    trbl: '%*68'
+  },
+  '*': {
+    xy: [181, 80, 240, 120],
+    trbl: '/*-9',
+    color: COLORS.OPERATOR
+  },
+  'R': {
+    xy: [0, 40, 60, 79],
+    trbl: 'RN7R',
+    color: COLORS.SPECIAL,
+    val: 'AC'
+  },
+  'N': {
+    xy: [60, 40, 120, 79],
+    trbl: 'N%8R',
+    color: COLORS.SPECIAL,
+    val: '+/-'
+  },
+  '%': {
+    xy: [120, 40, 180, 79],
+    trbl: '%/9N',
+    color: COLORS.SPECIAL
+  },
+  '/': {
+    xy: [181, 40, 240, 79],
+    trbl: '//*%',
+    color: COLORS.OPERATOR
+  }
+};
+
+var selected = DEFAULT_SELECTION;
+var prevSelected = DEFAULT_SELECTION;
+var prevNumber  = null;
+var currNumber = null;
+var operator = null;
+var results = null;
+var isDecimal = false;
+var hasPressedEquals = false;
+
+function drawKey(name, k, selected) {
+  var rMargin = 0;
+  var bMargin = 0;
+  var color = k.color || COLORS.DEFAULT;
+  g.setColor(color[selected ? 1 : 0]);
+  g.setFont('Vector', 20);
+  g.fillRect(k.xy[0], k.xy[1], k.xy[2], k.xy[3]);
+  g.setColor(-1);
+  // correct margins to center the texts
+  if (name == '0') {
+    rMargin = (RIGHT_MARGIN * 2) - 7;
+  } else if (name === '/') {
+    rMargin = 5;
+  } else if (name === '*') {
+    bMargin = 5;
+    rMargin = 3;
+  } else if (name === '-') {
+    rMargin = 3;
+  } else if (name === 'R' || name === 'N') {
+    rMargin = k.val === 'C' ? 0 : -9;
+  } else if (name === '%') {
+    rMargin = -3;
+  }
+  g.drawString(k.val || name, k.xy[0] + RIGHT_MARGIN + rMargin, k.xy[1] + BOTTOM_MARGIN + bMargin);
+}
+
+function doMath(x, y, operator) {
+  // might not be a number due to display of dot "." algo
+  x = Number(x);
+  y = Number(y);
+  switch (operator) {
+    case '/':
+      return x / y;
+    case '*':
+      return x * y;
+    case '+':
+      return x + y;
+    case '-':
+      return x - y;
+  }
+}
+
+function displayOutput(num) {
+  var len;
+  var minusMarge = 0;
+  g.setColor(0);
+  g.fillRect(0, 0, 240, 39);
+  g.setColor(-1);
+  if (num === Infinity || num === -Infinity || isNaN(num)) {
+    // handle division by 0
+    if (num === Infinity) {
+      num = 'INFINITY';
+    } else if (num === -Infinity) {
+      num = '-INFINITY';
+    } else {
+      num = 'NOT A NUMBER';
+      minusMarge = -25;
+    }
+    len = (num + '').length;
+    currNumber = null;
+    results = null;
+    isDecimal = false;
+    hasPressedEquals = false;
+    prevNumber = null;
+    operator = null;
+    keys.R.val = 'AC';
+    drawKey('R', keys.R);
+    g.setFont('Vector', 22);
+  } else {
+    // might not be a number due to display of dot "."
+    var numNumeric = Number(num);
+
+    if (typeof num === 'string') {
+      if (num.indexOf('.') !== -1) {
+        // display a 0 before a lonely dot
+        if (numNumeric == 0) {
+          num = '0.';
+        }
+      } else {
+        // remove preceding 0
+        while (num.length > 1 && num[0] === '0')
+          num = num.substr(1);
+      }
+    }
+
+    len = (num + '').length;
+    if (numNumeric < 0) {
+      // minus is not available in font 7x11Numeric7Seg, we use Vector
+      g.setFont('Vector', 20);
+      g.drawString('-', 220 - (len * 15), 10);
+      minusMarge = 15;
+    }
+    g.setFont('7x11Numeric7Seg', 2);
+  }
+  g.drawString(num, 220 - (len * 15) + minusMarge, 10);
+}
+
+function calculatorLogic(x) {
+  if (hasPressedEquals) {
+    currNumber = results;
+    prevNumber = null;
+    operator = null;
+    results = null;
+    isDecimal = null;
+    displayOutput(currNumber);
+    hasPressedEquals = false;
+  }
+  if (prevNumber != null && currNumber != null && operator != null) {
+    // we execute the calculus only when there was a previous number entered before and an operator
+    results = doMath(prevNumber, currNumber, operator);
+    operator = x;
+    prevNumber = results;
+    currNumber = null;
+    displayOutput(results);
+  } else if (prevNumber == null && currNumber != null && operator == null) {
+    // no operator yet, save the current number for later use when an operator is pressed
+    operator = x;
+    prevNumber = currNumber;
+    currNumber = null;
+    displayOutput(prevNumber);
+  } else if (prevNumber == null && currNumber == null && operator == null) {
+    displayOutput(0);
+  }
+}
+
+function buttonPress(val) {
+  switch (val) {
+    case 'R':
+      currNumber = null;
+      results = null;
+      isDecimal = false;
+      hasPressedEquals = false;
+      if (keys.R.val == 'AC') {
+        prevNumber = null;
+        operator = null;
+      } else {
+        keys.R.val = 'AC';
+        drawKey('R', keys.R);
+      }
+      displayOutput(0);
+      break;
+    case '%':
+      if (results != null) {
+        displayOutput(results /= 100);
+      } else if (currNumber != null) {
+        displayOutput(currNumber /= 100);
+      }
+      break;
+    case 'N':
+      if (results != null) {
+        displayOutput(results *= -1);
+      } else if (currNumber != null) {
+        displayOutput(currNumber *= -1);
+      }
+      break;
+    case '/':
+    case '*':
+    case '-':
+    case '+':
+      calculatorLogic(val);
+      break;
+    case '.':
+      keys.R.val = 'C';
+      drawKey('R', keys.R);
+      isDecimal = true;
+      displayOutput(currNumber == null ? 0 + '.' : currNumber + '.');
+      break;
+    case '=':
+      if (prevNumber != null && currNumber != null && operator != null) {
+        results = doMath(prevNumber, currNumber, operator);
+        prevNumber = results;
+        displayOutput(results);
+        hasPressedEquals = true;
+      }
+      break;
+    default:
+      keys.R.val = 'C';
+      drawKey('R', keys.R);
+      if (isDecimal) {
+        currNumber = currNumber == null ? 0 + '.' + val : currNumber + '.' + val;
+        isDecimal = false;
+      } else {
+        currNumber = currNumber == null ? val : currNumber + val;
+      }
+      displayOutput(currNumber);
+      break;
+  }
+}
+
+for (var k in keys) {
+  if (keys.hasOwnProperty(k)) {
+      drawKey(k, keys[k], k == '5');
+  }
+}
+g.setFont('7x11Numeric7Seg', 2.8);
+g.drawString('0', 205, 10);
+
+
+setWatch(function() {
+  drawKey(selected, keys[selected]);
+  // key 0 is 2 keys wide, go up to 1 if it was previously selected
+  if (selected == '0' && prevSelected === '1') {
+    prevSelected = selected;
+    selected = '1';
+  } else {
+    prevSelected = selected;
+    selected = keys[selected].trbl[0];
+  }
+  drawKey(selected, keys[selected], true);
+}, BTN1, {repeat: true, debounce: 100});
+
+setWatch(function() {
+  drawKey(selected, keys[selected]);
+  prevSelected = selected;
+  selected = keys[selected].trbl[2];
+  drawKey(selected, keys[selected], true);
+}, BTN3, {repeat: true, debounce: 100});
+
+Bangle.on('touch', function(direction) {
+  drawKey(selected, keys[selected]);
+  prevSelected = selected;
+  if (direction == 1) {
+    selected = keys[selected].trbl[3];
+  } else if (direction == 2) {
+    selected = keys[selected].trbl[1];
+  }
+  drawKey(selected, keys[selected], true);
+});
+
+setWatch(function() {
+  buttonPress(selected);
+}, BTN2, {repeat: true, debounce: 100});
diff --git a/apps/calculator/calculator-icon.js b/apps/calculator/calculator-icon.js
new file mode 100644
index 000000000..94158e7d2
--- /dev/null
+++ b/apps/calculator/calculator-icon.js
@@ -0,0 +1 @@
+require("heatshrink").decompress(atob("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"))
diff --git a/apps/calculator/calculator.png b/apps/calculator/calculator.png
new file mode 100644
index 000000000..8362c9200
Binary files /dev/null and b/apps/calculator/calculator.png differ