diff --git a/apps/choozi/ChangeLog b/apps/choozi/ChangeLog
index 03f7ef832..35adc7430 100644
--- a/apps/choozi/ChangeLog
+++ b/apps/choozi/ChangeLog
@@ -1,3 +1,9 @@
 0.01: New App!
 0.02: Support Bangle.js 2
 0.03: Fix bug for Bangle.js 2 where g.flip was not being called.
+0.04: Combine code for both apps
+      Better colors for Bangle.js 2
+      Fix selection animation for Bangle.js 2
+      New icon
+      Slightly wider arc segments for better visibility
+      Extract arc drawing code in library
diff --git a/apps/choozi/README.md b/apps/choozi/README.md
index f1e4255bc..ccaa97a27 100644
--- a/apps/choozi/README.md
+++ b/apps/choozi/README.md
@@ -11,16 +11,21 @@ the players seated in a circle, set the number of segments equal to the number
 of players, ensure that each person knows which colour represents them, and then
 choose a segment. After a short animation, the chosen segment will fill the screen.
 
-You can use Choozi to randomly select an element from any set with 2 to 13 members,
+You can use Choozi to randomly select an element from any set with 2 to 15 members,
 as long as you can define a bijection between members of the set and coloured
 segments on the Bangle.js display.
 
-## Controls
+## Controls Bangle 1
 
 BTN1: increase the number of segments
 BTN2: choose a segment at random
 BTN3: decrease the number of segments
 
+## Controls Bangle 2
+
+Swipe up/down: increase/decrease the number of segments
+BTN1 or tap: choose a segment at random
+
 ## Creator
 
 James Stanley
diff --git a/apps/choozi/app-icon.js b/apps/choozi/app-icon.js
index 51b3bead3..560286098 100644
--- a/apps/choozi/app-icon.js
+++ b/apps/choozi/app-icon.js
@@ -1 +1 @@
-require("heatshrink").decompress(atob("mEwggLIrnM4uqAAIhPgvMAAPFzIABzWgCxkMCweqC4QABDBYtC5QVFDBoWCCo5KLOQIWKDARFICxhJIFwOpC5owFFyAwGUYIuOGAwuRC4guSJAgXBCyIwDIyQXF5IXSzJeVMAReUAAOQhheTMAVcC6yOUC4aOUC7GZUyoXXzWqhQXVxGqC9mYC7OqC9eoxEKC6uBC6uIwAXBPCSmBwEAC6Z2BiAXBJCR2BgEAjQXSlGBC4JgSLwYABJCJGBLwJIDGB+IIwRIDGByNBIwZIDGBhdBRoQwSLoIuFGAYYKCwIuGGAgYI1QWBRgYYJMYmaFoSMEAAyrBAAgVCCxgYGjAWQAAMBC4UILZQA=="))
+require("heatshrink").decompress(atob("mEwwcH/4AW/u27dt2wQL/YOBCIXbv4QI+AODAQVsh4RHwEbCI0LCI9gCIOANAXbsFbG437tkDPg1btoRFFoILBgmSpMggECHQO/CAf2CIVJkgRBAQIjC24RFsECCItIgIRFMYMAiQRFpMAlqmDVwPYgAOEAQUggu274RD4BWCCIskCIPbCIPt20ABwwCCwARFgIRJyEWCIVt2EJCJi2BCJmSUgIRCwARNt/7CIIOICI1sWAwCFoFbCOtt8EACJsAgARR8hwBCJlJk4RlgARQAgIRKDwMn/gRBdJgRPyARBn4RBpARLiQRB/4RBgIRJwAREpIRLAYP///ypMgCJMACI0ECI4JCp4RB/wZECIsAAYN/CIP/5JPDCIhjDCIraHTIWTCAX//K7DCI+fCIf/EZA1CCAn//ipCLIsBk4RF/5ZHCIIQG//wPo8vCI//6QRFpYQIAAPpCIeXCBQAC/VfBI4="))
\ No newline at end of file
diff --git a/apps/choozi/app.js b/apps/choozi/app.js
index 1a5b2f17e..b9f53bc89 100644
--- a/apps/choozi/app.js
+++ b/apps/choozi/app.js
@@ -4,15 +4,16 @@
  *
  * James Stanley 2021
  */
-
-var colours = ['#ff0000', '#ff8080', '#00ff00', '#80ff80', '#0000ff', '#8080ff', '#ffff00', '#00ffff', '#ff00ff', '#ff8000', '#ff0080', '#8000ff', '#0080ff'];
+const GU = require("graphics_utils");
+var colours = ['#ff0000', '#00ff00', '#0000ff', '#ffff00', '#00ffff', '#ff00ff', '#ffffff'];
+var colours2 = ['#808080', '#404040', '#000040', '#004000', '#400000', '#ff8000', '#804000', '#4000c0'];
 
 var stepAngle = 0.18; // radians - resolution of polygon
 var gapAngle = 0.035; // radians - gap between segments
-var perimMin = 110; // px - min. radius of perimeter
-var perimMax = 120; // px - max. radius of perimeter
+var perimMin = g.getWidth()*0.40; // px - min. radius of perimeter
+var perimMax = g.getWidth()*0.49; // px - max. radius of perimeter
 
-var segmentMax = 106; // px - max radius of filled-in segment
+var segmentMax = g.getWidth()*0.38; // px - max radius of filled-in segment
 var segmentStep = 5; // px - step size of segment fill animation
 var circleStep = 4; // px - step size of circle fill animation
 
@@ -22,10 +23,10 @@ var minSpeed = 0.001; // rad/sec
 var animStartSteps = 300; // how many steps before it can start slowing?
 var accel = 0.0002; // rad/sec/sec - acc-/deceleration rate
 var ballSize = 3; // px - ball radius
-var ballTrack = 100; // px - radius of ball path
+var ballTrack = perimMin - ballSize*2; // px - radius of ball path
 
-var centreX = 120; // px - centre of screen
-var centreY = 120; // px - centre of screen
+var centreX = g.getWidth()*0.5; // px - centre of screen
+var centreY = g.getWidth()*0.5; // px - centre of screen
 
 var fontSize = 50; // px
 
@@ -33,7 +34,6 @@ var radians = 2*Math.PI; // radians per circle
 
 var defaultN = 3; // default value for N
 var minN = 2;
-var maxN = colours.length;
 var N;
 var arclen;
 
@@ -51,42 +51,14 @@ function shuffle (array) {
   }
 }
 
-// draw an arc between radii minR and maxR, and between
-// angles minAngle and maxAngle
-function arc(minR, maxR, minAngle, maxAngle) {
-  var step = stepAngle;
-  var angle = minAngle;
-  var inside = [];
-  var outside = [];
-  var c, s;
-  while (angle < maxAngle) {
-    c = Math.cos(angle);
-    s = Math.sin(angle);
-    inside.push(centreX+c*minR); // x
-    inside.push(centreY+s*minR); // y
-    // outside coordinates are built up in reverse order
-    outside.unshift(centreY+s*maxR); // y
-    outside.unshift(centreX+c*maxR); // x
-    angle += step;
-  }
-  c = Math.cos(maxAngle);
-  s = Math.sin(maxAngle);
-  inside.push(centreX+c*minR);
-  inside.push(centreY+s*minR);
-  outside.unshift(centreY+s*maxR);
-  outside.unshift(centreX+c*maxR);
-  
-  var vertices = inside.concat(outside);
-  g.fillPoly(vertices, true);
-}
-
 // draw the arc segments around the perimeter
 function drawPerimeter() {
+  g.setBgColor('#000000');
   g.clear();
   for (var i = 0; i < N; i++) {
     g.setColor(colours[i%colours.length]);
     var minAngle = (i/N)*radians;
-    arc(perimMin,perimMax,minAngle,minAngle+arclen);
+    GU.fillArc(g, centreX, centreY, perimMin,perimMax,minAngle,minAngle+arclen, stepAngle);
   }
 }
 
@@ -131,6 +103,7 @@ function animateChoice(target) {
     g.fillCircle(x, y, ballSize);
     oldx=x;
     oldy=y;
+    if (process.env.HWVERSION == 2) g.flip();
   }
 }
 
@@ -141,11 +114,15 @@ function choose() {
   var maxAngle = minAngle + arclen;
   animateChoice((minAngle+maxAngle)/2);
   g.setColor(colours[chosen%colours.length]);
-  for (var i = segmentMax-segmentStep; i >= 0; i -= segmentStep)
-    arc(i, perimMax, minAngle, maxAngle);
-  arc(0, perimMax, minAngle, maxAngle);
-  for (var r = 1; r < segmentMax; r += circleStep)
+  for (var i = segmentMax-segmentStep; i >= 0; i -= segmentStep){
+    GU.fillArc(g, centreX, centreY, i, perimMax, minAngle, maxAngle, stepAngle);
+    if (process.env.HWVERSION == 2) g.flip();
+  }
+  GU.fillArc(g, centreX, centreY, 0, perimMax, minAngle, maxAngle, stepAngle);
+  for (var r = 1; r < segmentMax; r += circleStep){
     g.fillCircle(centreX,centreY,r);
+    if (process.env.HWVERSION == 2) g.flip();
+  }
   g.fillCircle(centreX,centreY,segmentMax);
 }
 
@@ -171,38 +148,47 @@ function setN(n) {
   drawPerimeter();
 }
 
-// save N to choozi.txt
+// save N to choozi.save
 function writeN() {
-  var file = require("Storage").open("choozi.txt","w");
-  file.write(N);
+  var savedN = read();
+  if (savedN != N) require("Storage").write("choozi.save","" + N);
 }
 
-// load N from choozi.txt
+function read(){
+  var n = require("Storage").read("choozi.save");
+  if (n !== undefined) return parseInt(n);
+  return defaultN;
+}
+
+// load N from choozi.save
 function readN() {
-  var file = require("Storage").open("choozi.txt","r");
-  var n = file.readLine();
-  if (n !== undefined) setN(parseInt(n));
-  else setN(defaultN);
+  setN(read());
 }
 
-shuffle(colours); // is this really best?
-Bangle.setLCDMode("direct");
-Bangle.setLCDTimeout(0); // keep screen on
+if (process.env.HWVERSION == 1){
+  colours=colours.concat(colours2);
+  shuffle(colours);
+} else {
+  shuffle(colours);
+  shuffle(colours2);
+  colours=colours.concat(colours2);
+}
+
+var maxN = colours.length;
+if (process.env.HWVERSION == 1){
+  Bangle.setLCDMode("direct");
+  Bangle.setLCDTimeout(0); // keep screen on
+}
 readN();
 drawN();
 
-setWatch(() => {
-  setN(N+1);
-  drawN();
-}, BTN1, {repeat:true});
-
-setWatch(() => {
-  writeN();
-  drawPerimeter();
-  choose();
-}, BTN2, {repeat:true});
-
-setWatch(() => {
-  setN(N-1);
-  drawN();
-}, BTN3, {repeat:true});
+Bangle.setUI("updown", (v)=>{
+  if (!v){
+    writeN();
+    drawPerimeter();
+    choose();
+  } else {
+    setN(N-v);
+    drawN();
+  }
+});
diff --git a/apps/choozi/app.png b/apps/choozi/app.png
index 99c9fa07a..50f09f164 100644
Binary files a/apps/choozi/app.png and b/apps/choozi/app.png differ
diff --git a/apps/choozi/appb2.js b/apps/choozi/appb2.js
deleted file mode 100644
index 5f217f638..000000000
--- a/apps/choozi/appb2.js
+++ /dev/null
@@ -1,207 +0,0 @@
-/* Choozi - Choose people or things at random using Bangle.js.
- * Inspired by the "Chwazi" Android app
- *
- * James Stanley 2021
- */
-
-var colours = ['#ff0000', '#ff8080', '#00ff00', '#80ff80', '#0000ff', '#8080ff', '#ffff00', '#00ffff', '#ff00ff', '#ff8000', '#ff0080', '#8000ff', '#0080ff'];
-
-var stepAngle = 0.18; // radians - resolution of polygon
-var gapAngle = 0.035; // radians - gap between segments
-var perimMin = 80; // px - min. radius of perimeter
-var perimMax = 87; // px - max. radius of perimeter
-
-var segmentMax = 70; // px - max radius of filled-in segment
-var segmentStep = 5; // px - step size of segment fill animation
-var circleStep = 4; // px - step size of circle fill animation
-
-// rolling ball animation:
-var maxSpeed = 0.08; // rad/sec
-var minSpeed = 0.001; // rad/sec
-var animStartSteps = 300; // how many steps before it can start slowing?
-var accel = 0.0002; // rad/sec/sec - acc-/deceleration rate
-var ballSize = 3; // px - ball radius
-var ballTrack = 75; // px - radius of ball path
-
-var centreX = 88; // px - centre of screen
-var centreY = 88; // px - centre of screen
-
-var fontSize = 50; // px
-
-var radians = 2*Math.PI; // radians per circle
-
-var defaultN = 3; // default value for N
-var minN = 2;
-var maxN = colours.length;
-var N;
-var arclen;
-
-// https://www.frankmitchell.org/2015/01/fisher-yates/
-function shuffle (array) {
-  var i = 0
-    , j = 0
-    , temp = null;
-
-  for (i = array.length - 1; i > 0; i -= 1) {
-    j = Math.floor(Math.random() * (i + 1));
-    temp = array[i];
-    array[i] = array[j];
-    array[j] = temp;
-  }
-}
-
-// draw an arc between radii minR and maxR, and between
-// angles minAngle and maxAngle
-function arc(minR, maxR, minAngle, maxAngle) {
-  var step = stepAngle;
-  var angle = minAngle;
-  var inside = []; 
-  var outside = [];
-  var c, s;
-  while (angle < maxAngle) {
-    c = Math.cos(angle);
-    s = Math.sin(angle);
-    inside.push(centreX+c*minR); // x
-    inside.push(centreY+s*minR); // y
-    // outside coordinates are built up in reverse order
-    outside.unshift(centreY+s*maxR); // y
-    outside.unshift(centreX+c*maxR); // x
-    angle += step;
-  }
-  c = Math.cos(maxAngle);
-  s = Math.sin(maxAngle);
-  inside.push(centreX+c*minR);
-  inside.push(centreY+s*minR);
-  outside.unshift(centreY+s*maxR);
-  outside.unshift(centreX+c*maxR);
-
-  var vertices = inside.concat(outside);
-  g.fillPoly(vertices, true);
-}
-
-// draw the arc segments around the perimeter
-function drawPerimeter() {
-  g.clear();
-  for (var i = 0; i < N; i++) {
-    g.setColor(colours[i%colours.length]);
-    var minAngle = (i/N)*radians;
-    arc(perimMin,perimMax,minAngle,minAngle+arclen);
-  }
-}
-
-// animate a ball rolling around and settling at "target" radians
-function animateChoice(target) {
-  var angle = 0;
-  var speed = 0;
-  var oldx = -10;
-  var oldy = -10;
-  var decelFromAngle = -1;
-  var allowDecel = false;
-  for (var i = 0; true; i++) {
-    angle = angle + speed;
-    if (angle > radians) angle -= radians;
-    if (i < animStartSteps || (speed < maxSpeed && !allowDecel)) {
-      speed = speed + accel;
-      if (speed > maxSpeed) {
-        speed = maxSpeed;
-        /* when we reach max speed, we know how long it takes
-         * to accelerate, and therefore how long to decelerate, so
-         * we can work out what angle to start decelerating from */
-        if (decelFromAngle < 0) {
-          decelFromAngle = target-angle;
-          while (decelFromAngle < 0) decelFromAngle += radians;
-          while (decelFromAngle > radians) decelFromAngle -= radians;
-        }
-      }
-    } else {
-      if (!allowDecel && (angle < decelFromAngle) && (angle+speed >= decelFromAngle)) allowDecel = true;
-      if (allowDecel) speed = speed - accel;
-      if (speed < minSpeed) speed = minSpeed;
-      if (speed == minSpeed && angle < target && angle+speed >= target) return;
-    }
-
-    var r = i/2;
-    if (r > ballTrack) r = ballTrack;
-    var x = centreX+Math.cos(angle)*r;
-    var y = centreY+Math.sin(angle)*r;
-    g.setColor('#000000');
-    g.fillCircle(oldx,oldy,ballSize+1);
-    g.setColor('#ffffff');
-    g.fillCircle(x, y, ballSize);
-    oldx=x;
-    oldy=y;
-    g.flip();
-  }
-}
-
-// choose a winning segment and animate its selection
-function choose() {
-  var chosen = Math.floor(Math.random()*N);
-  var minAngle = (chosen/N)*radians;
-  var maxAngle = minAngle + arclen;
-  animateChoice((minAngle+maxAngle)/2);
-  g.setColor(colours[chosen%colours.length]);
-  for (var i = segmentMax-segmentStep; i >= 0; i -= segmentStep)
-    arc(i, perimMax, minAngle, maxAngle);
-  arc(0, perimMax, minAngle, maxAngle);
-  for (var r = 1; r < segmentMax; r += circleStep)
-    g.fillCircle(centreX,centreY,r);
-  g.fillCircle(centreX,centreY,segmentMax);
-}
-
-// draw the current value of N in the middle of the screen, with
-// up/down arrows
-function drawN() {
-  g.setColor(g.theme.fg);
-  g.setFont("Vector",fontSize);
-  g.drawString(N,centreX-g.stringWidth(N)/2+4,centreY-fontSize/2);
-  if (N < maxN)
-    g.fillPoly([centreX-6,centreY-fontSize/2-7, centreX+6,centreY-fontSize/2-7, centreX, centreY-fontSize/2-14]);
-  if (N > minN)
-    g.fillPoly([centreX-6,centreY+fontSize/2+5, centreX+6,centreY+fontSize/2+5, centreX, centreY+fontSize/2+12]);
-}
-
-// update number of segments, with min/max limit, "arclen" update,
-// and screen reset
-function setN(n) {
-  N = n;
-  if (N < minN) N = minN;
-  if (N > maxN) N = maxN;
-  arclen = radians/N - gapAngle;
-  drawPerimeter();
-}
-
-// save N to choozi.txt
-function writeN() {
-  var file = require("Storage").open("choozi.txt","w");
-  file.write(N);
-}
-
-// load N from choozi.txt
-function readN() {
-  var file = require("Storage").open("choozi.txt","r");
-  var n = file.readLine();
-  if (n !== undefined) setN(parseInt(n));
-  else setN(defaultN);
-}
-
-shuffle(colours); // is this really best?
-Bangle.setLCDTimeout(0); // keep screen on
-readN();
-drawN();
-
-setWatch(() => {
-  writeN();
-  drawPerimeter();
-  choose();
-}, BTN1, {repeat:true});
-
-Bangle.on('touch', function(zone,e) {
-  if(e.x>+88){
-    setN(N-1);
-    drawN();
-  }else{
-    setN(N+1);
-    drawN();
-  }
-});
diff --git a/apps/choozi/bangle1-choozi-screenshot1.png b/apps/choozi/bangle1-choozi-screenshot1.png
index 104024958..ee422ed10 100644
Binary files a/apps/choozi/bangle1-choozi-screenshot1.png and b/apps/choozi/bangle1-choozi-screenshot1.png differ
diff --git a/apps/choozi/bangle1-choozi-screenshot2.png b/apps/choozi/bangle1-choozi-screenshot2.png
index f3b6868bf..20edf4c78 100644
Binary files a/apps/choozi/bangle1-choozi-screenshot2.png and b/apps/choozi/bangle1-choozi-screenshot2.png differ
diff --git a/apps/choozi/metadata.json b/apps/choozi/metadata.json
index 79af76fa2..c42abe079 100644
--- a/apps/choozi/metadata.json
+++ b/apps/choozi/metadata.json
@@ -1,7 +1,7 @@
 {
   "id": "choozi",
   "name": "Choozi",
-  "version": "0.03",
+  "version": "0.04",
   "description": "Choose people or things at random using Bangle.js.",
   "icon": "app.png",
   "tags": "tool",
@@ -10,8 +10,10 @@
   "allow_emulator": true,
   "screenshots": [{"url":"bangle1-choozi-screenshot1.png"},{"url":"bangle1-choozi-screenshot2.png"}],
   "storage": [
-    {"name":"choozi.app.js","url":"app.js","supports": ["BANGLEJS"]},
-    {"name":"choozi.app.js","url":"appb2.js","supports": ["BANGLEJS2"]},
+    {"name":"choozi.app.js","url":"app.js"},
     {"name":"choozi.img","url":"app-icon.js","evaluate":true}
+  ],
+  "data": [
+    {"name":"choozi.save"}
   ]
 }
diff --git a/modules/graphics_utils.js b/modules/graphics_utils.js
new file mode 100644
index 000000000..5c08188bc
--- /dev/null
+++ b/modules/graphics_utils.js
@@ -0,0 +1,35 @@
+// draw an arc between radii minR and maxR, and between angles minAngle and maxAngle centered at X,Y. All angles are radians.
+exports.fillArc = function(graphics, X, Y, minR, maxR, minAngle, maxAngle, stepAngle) {
+  var step = stepAngle || 0.2;
+  var angle = minAngle;
+  var inside = [];
+  var outside = [];
+  var c, s;
+  while (angle < maxAngle) {
+    c = Math.cos(angle);
+    s = Math.sin(angle);
+    inside.push(X+c*minR); // x
+    inside.push(Y+s*minR); // y
+    // outside coordinates are built up in reverse order
+    outside.unshift(Y+s*maxR); // y
+    outside.unshift(X+c*maxR); // x
+    angle += step;
+  }
+  c = Math.cos(maxAngle);
+  s = Math.sin(maxAngle);
+  inside.push(X+c*minR);
+  inside.push(Y+s*minR);
+  outside.unshift(Y+s*maxR);
+  outside.unshift(X+c*maxR);
+
+  var vertices = inside.concat(outside);
+  graphics.fillPoly(vertices, true);
+}
+
+exports.degreesToRadians = function(degrees){
+  return Math.PI/180 * degrees;
+}
+
+exports.radiansToDegrees = function(radians){
+  return 180/Math.PI * degrees;
+}
\ No newline at end of file