diff --git a/cmds/cmds.ts b/cmds/cmds.ts
deleted file mode 100644
index 6e5e1fec..00000000
--- a/cmds/cmds.ts
+++ /dev/null
@@ -1,60 +0,0 @@
-/// <reference path="../node_modules/pxt-core/typings/node/node.d.ts"/>
-/// <reference path="../node_modules/pxt-core/built/pxtlib.d.ts" />
-
-import * as fs from "fs";
-import * as path from "path";
-import * as child_process from "child_process";
-
-let writeFileAsync: any = Promise.promisify(fs.writeFile)
-let execAsync: (cmd: string, options?: { cwd?: string }) => Promise<Buffer> = Promise.promisify(child_process.exec)
-let readDirAsync = Promise.promisify(fs.readdir)
-
-
-export function deployCoreAsync(res: ts.pxtc.CompileResult) {
-    return getBitDrivesAsync()
-        .then(drives => {
-            if (drives.length == 0) {
-                console.log("cannot find any drives to deploy to");
-                return Promise.resolve(0);
-            }
-
-            console.log(`copy ${ts.pxtc.BINARY_HEX} to ` + drives.join(", "));
-
-            let writeHexFile = (filename: string) => {
-                return writeFileAsync(filename + ts.pxtc.BINARY_HEX, res.outfiles[ts.pxtc.BINARY_HEX])
-                    .then(() => console.log("wrote hex file to " + filename));
-            };
-
-            return Promise.map(drives, d => writeHexFile(d))
-                .then(() => drives.length);
-        });
-}
-
-function getBitDrivesAsync(): Promise<string[]> {
-    if (process.platform == "win32") {
-        const rx = new RegExp("^([A-Z]:).* " + pxt.appTarget.compile.deployDrives)
-        return execAsync("wmic PATH Win32_LogicalDisk get DeviceID, VolumeName, FileSystem")
-            .then(buf => {
-                let res: string[] = []
-                buf.toString("utf8").split(/\n/).forEach(ln => {
-                    let m = rx.exec(ln)
-                    if (m) {
-                        res.push(m[1] + "/")
-                    }
-                })
-                return res
-            })
-    }
-    else if (process.platform == "darwin") {
-        const rx = new RegExp(pxt.appTarget.compile.deployDrives)
-        return readDirAsync("/Volumes")
-            .then(lst => lst.filter(s => rx.test(s)).map(s => "/Volumes/" + s + "/"))
-    } else if (process.platform == "linux") {
-        const rx = new RegExp(pxt.appTarget.compile.deployDrives)
-        const user = process.env["USER"]
-        return readDirAsync(`/media/${user}`)
-            .then(lst => lst.filter(s => rx.test(s)).map(s => `/media/${user}/${s}/`))
-    } else {
-        return Promise.resolve([])
-    }
-}
diff --git a/cmds/pxtrequire.ts b/cmds/pxtrequire.ts
index 26442585..227781fb 100644
--- a/cmds/pxtrequire.ts
+++ b/cmds/pxtrequire.ts
@@ -1,3 +1,6 @@
+/// <reference path="../node_modules/pxt-core/typings/node/node.d.ts"/>
+/// <reference path="../node_modules/pxt-core/built/pxtlib.d.ts" />
+
 import * as path from "path";
 export let pxtCore = require("pxt-core");
 // require.resolve() gives path to [pxt dir]/built/pxt.js, so move up twice to get pxt root dir
diff --git a/docs/index-ref.json b/docs/index-ref.json
index 9f6ae978..6534e86d 100644
--- a/docs/index-ref.json
+++ b/docs/index-ref.json
@@ -1,3 +1,3 @@
 {
-    "appref": "v0.6.13"
+    "appref": "v0.6.36"
 }
diff --git a/docs/projects/compass.md b/docs/projects/compass.md
index f22ffe04..38c6667c 100644
--- a/docs/projects/compass.md
+++ b/docs/projects/compass.md
@@ -10,12 +10,10 @@ Welcome! This guided tutorial will show you how to program a script that display
 
 ### ~
 
-
 ## Step 1
 
 Create a loop that will continuously update the reading of the compass.
 
-
 ```blocks
 basic.forever(() => {
     
diff --git a/docs/projects/flashing-heart.md b/docs/projects/flashing-heart.md
index 95f612b1..40be3ba3 100644
--- a/docs/projects/flashing-heart.md
+++ b/docs/projects/flashing-heart.md
@@ -2,8 +2,7 @@
 
 ### ~avatar avatar
 
-Use the LEDs to display a flashing heart, and then create
-an animation of a broken heart. :(
+Use the LEDs to display a flashing heart!
 
 ### ~
 
@@ -38,19 +37,19 @@ basic.clearScreen();
 
 ## Step 3
 
-Put a [forever loop](/reference/basic/forever) around it.
+Put a [forever loop](/reference/basic/forever) around it to repeat the animation.
 
 ```blocks
 basic.forever(() => {
-basic.showLeds(`
-    . # . # .
-    # # # # #
-    # # # # #
-    . # # # .
-    . . # . .`
-    );
-basic.pause(500);
-basic.clearScreen();
+    basic.showLeds(`
+        . # . # .
+        # # # # #
+        # # # # #
+        . # # # .
+        . . # . .`
+        );
+    basic.pause(500);
+    basic.clearScreen();
 })
 ```
 
@@ -60,45 +59,50 @@ Add a [pause](/reference/basic/pause) to wait after clearing the screen.
 
 ```blocks
 basic.forever(() => {
-basic.showLeds(`
-    . # . # .
-    # # # # #
-    # # # # #
-    . # # # .
-    . . # . .`
-    );
-basic.pause(500);
-basic.clearScreen();
-basic.pause(500);
+    basic.showLeds(`
+        . # . # .
+        # # # # #
+        # # # # #
+        . # # # .
+        . . # . .`
+        );
+    basic.pause(500);
+    basic.clearScreen();
+    basic.pause(500);
 })
 ```
 
-## Step 5
+## Send your heartbeats over radio!
 
-Add a second image of a broken heart. 
+Do you have a second @boardname@ at hand? You could use radio and send your heartbeats to other
+@boardname@ and show a heart when you receive one.
 
+* move the code in the **forever** inside 
+a [on data packet received](/reference/radio/on-data-packet-received) handler. 
+The handler will run whenever a message is received from another @boardname@.
+* use [send number](/reference/radio/send-number) and [pause](/reference/basic/pause) 
+to broadcast a packet of data every second.
 
 ```blocks
 basic.forever(() => {
-basic.showLeds(`
-    . # . # .
-    # # # # #
-    # # # # #
-    . # # # .
-    . . # . .`
-    );
-basic.pause(500);
-basic.clearScreen();
-basic.pause(500);
-basic.showLeds(`
-    . # . # .
-    # . # # #
-    # . . . #
-    . # # # .
-    . . # . .`
-    );
-basic.pause(500);
-basic.clearScreen();
-basic.pause(500);
+    radio.sendNumber(0)
+    basic.pause(1000)
+})
+radio.onDataPacketReceived(({receivedNumber}) => {
+    basic.showLeds(`
+        . # . # .
+        # # # # #
+        # # # # #
+        . # # # .
+        . . # . .`);
+    basic.pause(500)
+    basic.clearScreen()
+    basic.pause(500)
 })
 ```
+
+Download the .hex file onto both @boardname@ and try it out!
+
+```package
+radio
+```
\ No newline at end of file
diff --git a/docs/projects/smiley-buttons.md b/docs/projects/smiley-buttons.md
index f7eb51cb..2b0ff343 100644
--- a/docs/projects/smiley-buttons.md
+++ b/docs/projects/smiley-buttons.md
@@ -12,8 +12,8 @@ Use [show leds](/reference/basic/show-leds) to make a smiley face:
 
 ```blocks
 basic.showLeds(`
-    . # . # .
-    . # . # .
+    # # . # #
+    # # . # #
     . . . . .
     # . . . #
     . # # # .`
@@ -22,56 +22,93 @@ basic.showLeds(`
 
 ## Step 2
 
-Add an input block for when [button A is pressed](/reference/input/button-is-pressed), and put a
-frowny face inside it:
+Add an input block for when [button A is pressed](/reference/input/button-is-pressed), 
+and **move** the smiley face inside it:
 
 ```blocks
-basic.showLeds(`
-    . # . # .
-    . # . # .
-    . . . . .
-    # . . . #
-    . # # # .`
-    );
 input.onButtonPressed(Button.A, () => { 
     basic.showLeds(`
-        . # . # .
-        . # . # .
-        . . . . .
-        . # # # .
-        # . . . #`
-        );
-});
-```
-
-## Step 3
-
-Now add blocks so that when [button B is pressed](/reference/input/button-is-pressed), a smiley appears:
-
-```blocks
-basic.showLeds(`
-    . # . # .
-    . # . # .
-    . . . . .
-    # . . . #
-    . # # # .`
-    );
-input.onButtonPressed(Button.A, () => { 
-    basic.showLeds(`
-        . # . # .
-        . # . # .
-        . . . . .
-        . # # # .
-        # . . . #`
-        );
-});
-input.onButtonPressed(Button.B, () => { 
-    basic.showLeds(`
-        . # . # .
-        . # . # .
+        # # . # #
+        # # . # #
         . . . . .
         # . . . #
         . # # # .`
         );
 });
 ```
+
+Try pressing button A!
+
+## Step 3
+
+Now add blocks so that when [button B is pressed](/reference/input/on-button-pressed), 
+a frowney appears:
+
+```blocks
+input.onButtonPressed(Button.A, () => { 
+    basic.showLeds(`
+        # # . # #
+        # # . # #
+        . . . . .
+        # . . . #
+        . # # # .`
+        );
+});
+input.onButtonPressed(Button.B, () => { 
+    basic.showLeds(`
+        # # . # #
+        # # . # #
+        . . . . .
+        . # # # .
+        # . . . #`
+        );
+});
+```
+
+Try pressing ``A`` or ``B``!
+
+## Send your smileys over radio
+
+Do you have a second @boardname@ at hand? You could use radio and send your smileys or frownies to other
+@boardname@.
+
+Since radio can send numbers, we decide that ``0`` is the code for displaying a smiley 
+and ``1`` is the code for a frowney.
+
+Change your code as follows: 
+* [radio send number](/reference/radio/send-number) sends a number
+to any other @boardname@ in range
+* [radio on data packet received](/reference/radio/on-data-packet-received) runs code
+when data is received over radio
+
+```blocks
+input.onButtonPressed(Button.A, () => {
+    radio.sendNumber(0)
+})
+input.onButtonPressed(Button.B, () => {
+    radio.sendNumber(1)
+})
+radio.onDataPacketReceived(({receivedNumber}) => {
+    if (receivedNumber == 0) {
+        basic.showLeds(`
+            # # . # #
+            # # . # #
+            . . . . .
+            # . . . #
+            . # # # .
+            `)
+    } else {
+        basic.showLeds(`
+            # # . # #
+            # # . # #
+            . . . . .
+            . # # # .
+            # . . . #
+            `)
+    }
+})
+```
+
+```package
+radio
+```
diff --git a/docs/reference/bluetooth/advertise-url.md b/docs/reference/bluetooth/advertise-url.md
index 9a0a808d..852f4090 100644
--- a/docs/reference/bluetooth/advertise-url.md
+++ b/docs/reference/bluetooth/advertise-url.md
@@ -18,18 +18,18 @@ Read more at https://lancaster-university.github.io/microbit-docs/ble/eddystone/
 ## ~
 
 ```sig
-bluetooth.advertiseUrl("https://pxt.microbit.org/", 7);
+bluetooth.advertiseUrl("https://pxt.microbit.org/", 7, true);
 ```
 
 ### Parameters
 
-* ``url`` - a [string](/reference/types/string) containing the URL to broadcast, at most 18 characters long
+* ``url`` - a [string](/reference/types/string) containing the URL to broadcast, at most 17 characters long, excluding the protocol (eg: ``https://``) which gets encoded as 1 byte.
 * ``power`` - a [number](/reference/types/number) representing the power level between 0 (short) and 7 (maximum range).
 
 ### Example: Broadcast a secret code
 
 ```blocks
-bluetooth.advertiseUrl("https://pxt.io?secret=42", 7);
+bluetooth.advertiseUrl("https://pxt.io?secret=42", 7, true);
 ```
 
 ## See Also
@@ -38,4 +38,4 @@ bluetooth.advertiseUrl("https://pxt.io?secret=42", 7);
 
 ```package
 bluetooth
-```
\ No newline at end of file
+```
diff --git a/docs/reference/serial/read-until.md b/docs/reference/serial/read-until.md
new file mode 100644
index 00000000..4303b30b
--- /dev/null
+++ b/docs/reference/serial/read-until.md
@@ -0,0 +1,28 @@
+# Serial Read Until
+
+Read a text from the serial port until a delimiter is found.
+
+```sig
+serial.readUntil(",");
+```
+
+### Returns
+
+* a [string](/reference/types/string) containing input from the serial port, such as a response typed by a user
+
+### Example
+
+The following example reads strings separated by commands (``,``).
+
+```blocks
+basic.forever(() => {
+    let answer = serial.readUntil(",");
+    serial.writeLine(answer);
+});
+```
+
+### See also
+
+[serial](/device/serial),
+[serial write line](/reference/serial/write-line),
+[serial write value](/reference/serial/write-value)
diff --git a/docs/uploader.md b/docs/uploader.md
index 165ccb56..587c9ddb 100644
--- a/docs/uploader.md
+++ b/docs/uploader.md
@@ -38,7 +38,7 @@ That's it!
 
 ### Installation Instructions
 
-* Download the [Microsoft.Uploader.Microbit.zip](https://pxt.microbit.org/microbit-uploader.zip) file to your local computer.
+* Download the [Microsoft.Uploader.Microbit.zip](https://www.touchdevelop.com/microbituploader.zip) file to your local computer.
 * Unzip the .zip file to your desktop.
 * Launch the Microsoft.Uploader.exe file before working on your @boardname@.
 
diff --git a/libs/core/_locales/core-jsdoc-strings.json b/libs/core/_locales/core-jsdoc-strings.json
index 7b23ac25..44b19763 100644
--- a/libs/core/_locales/core-jsdoc-strings.json
+++ b/libs/core/_locales/core-jsdoc-strings.json
@@ -85,7 +85,7 @@
   "game.setLife": "Sets the current life value",
   "game.setLife|param|value": "TODO",
   "game.setScore": "Sets the current score value",
-  "game.setScore|param|value": "TODO",
+  "game.setScore|param|value": "new score value.",
   "game.showScore": "Displays the score on the screen.",
   "game.startCountdown": "Starts a game countdown timer",
   "game.startCountdown|param|ms": "countdown duration in milliseconds, eg: 10000",
diff --git a/libs/core/_locales/core-strings.json b/libs/core/_locales/core-strings.json
index 264fced3..080f1221 100644
--- a/libs/core/_locales/core-strings.json
+++ b/libs/core/_locales/core-strings.json
@@ -110,6 +110,7 @@
   "game.createSprite|block": "create sprite at|x: %x|y: %y",
   "game.gameOver|block": "game over",
   "game.score|block": "score",
+  "game.setScore|block": "set score %points",
   "game.startCountdown|block": "start countdown|(ms) %duration",
   "game|block": "game",
   "images.createBigImage|block": "create big image",
diff --git a/libs/core/game.ts b/libs/core/game.ts
index ccd36552..d16642a7 100644
--- a/libs/core/game.ts
+++ b/libs/core/game.ts
@@ -40,7 +40,7 @@ namespace game {
      * @param x sprite horizontal coordinate, eg: 2
      * @param y sprite vertical coordinate, eg: 2
      */
-    //% weight=60
+    //% weight=60 blockGap=8
     //% blockId=game_create_sprite block="create sprite at|x: %x|y: %y"
     //% parts="ledmatrix"
     export function createSprite(x: number, y: number): LedSprite {
@@ -146,8 +146,9 @@ namespace game {
 
     /**
      * Sets the current score value
-     * @param value TODO
+     * @param value new score value.
      */
+    //% blockId=game_set_score block="set score %points" blockGap=8
     //% weight=10 help=game/set-score
     export function setScore(value: number): void {
         _score = Math.max(0, value);
@@ -646,6 +647,7 @@ namespace game {
          * Deletes the sprite from the game engine. All further operation of the sprite will not have any effect.
          * @param this sprite to delete
          */
+        //% weight=59
         //% blockId="game_delete_sprite" block="delete %this"        
         public delete(): void {
             sprites.removeElement(this);
diff --git a/libs/core/pxt.cpp b/libs/core/pxt.cpp
index 5295de84..af031013 100644
--- a/libs/core/pxt.cpp
+++ b/libs/core/pxt.cpp
@@ -131,7 +131,9 @@ namespace pxt {
           if (refmask[i]) decr(r->fields[i]);
           r->fields[i] = 0;
         }
-        delete r;
+        //RefRecord is allocated using placement new
+        r->~RefRecord();
+        ::operator delete(r);
     }
 
     void RefRecord_print(RefRecord *r)
@@ -259,7 +261,9 @@ namespace pxt {
         decr(fields[i]);
         fields[i] = 0;
       }
-      delete this;
+      //RefAction is allocated using placement new
+      this->~RefAction();
+      ::operator delete(this);
     }
 
     void RefAction::print()
diff --git a/package.json b/package.json
index 57c651f9..dc15db6a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "pxt-microbit",
-  "version": "0.6.31",
+  "version": "0.6.36",
   "description": "micro:bit target for PXT",
   "keywords": [
     "JavaScript",
@@ -34,6 +34,6 @@
     "semantic-ui-less": "^2.2.4"
   },
   "dependencies": {
-    "pxt-core": "0.5.91"
+    "pxt-core": "0.5.99"
   }
 }
diff --git a/sim/state/accelerometer.ts b/sim/state/accelerometer.ts
index 8bc42bd4..18d3d588 100644
--- a/sim/state/accelerometer.ts
+++ b/sim/state/accelerometer.ts
@@ -23,15 +23,15 @@ namespace pxsim.input {
     }
 
     export function rotation(kind: number): number {
-        let b = board().accelerometerState;
-        let acc = b.accelerometer;
+        const b = board().accelerometerState;
+        const acc = b.accelerometer;
         acc.activate();
-        let x = acc.getX(MicroBitCoordinateSystem.NORTH_EAST_DOWN);
-        let y = acc.getX(MicroBitCoordinateSystem.NORTH_EAST_DOWN);
-        let z = acc.getX(MicroBitCoordinateSystem.NORTH_EAST_DOWN);
+        const x = acc.getX(MicroBitCoordinateSystem.NORTH_EAST_DOWN);
+        const y = acc.getY(MicroBitCoordinateSystem.NORTH_EAST_DOWN);
+        const z = acc.getZ(MicroBitCoordinateSystem.NORTH_EAST_DOWN);
 
-        let roll = Math.atan2(y, z);
-        let pitch = Math.atan(-x / (y * Math.sin(roll) + z * Math.cos(roll)));
+        const roll = Math.atan2(y, z);
+        const pitch = Math.atan(-x / (y * Math.sin(roll) + z * Math.cos(roll)));
 
         let r = 0;
         switch (kind) {
diff --git a/sim/visuals/microbit.ts b/sim/visuals/microbit.ts
index 116ac6d9..0a2ece48 100644
--- a/sim/visuals/microbit.ts
+++ b/sim/visuals/microbit.ts
@@ -556,12 +556,12 @@ namespace pxsim.visuals {
 
         private updateTilt() {
             if (this.props.disableTilt) return;
-            let state = this.board;
+            const state = this.board;
             if (!state || !state.accelerometerState.accelerometer.isActive) return;
 
-            let x = state.accelerometerState.accelerometer.getX();
-            let y = state.accelerometerState.accelerometer.getY();
-            let af = 8 / 1023;
+            const x = state.accelerometerState.accelerometer.getX();
+            const y = -state.accelerometerState.accelerometer.getY();
+            const af = 8 / 1023;
 
             this.element.style.transform = "perspective(30em) rotateX(" + y * af + "deg) rotateY(" + x * af + "deg)"
             this.element.style.perspectiveOrigin = "50% 50% 50%";
@@ -704,7 +704,7 @@ namespace pxsim.visuals {
             }
             let tiltDecayer = 0;
             this.element.addEventListener(pointerEvents.move, (ev: MouseEvent) => {
-                let state = this.board;
+                const state = this.board;
                 if (!state.accelerometerState.accelerometer.isActive) return;
 
                 if (tiltDecayer) {
@@ -712,14 +712,14 @@ namespace pxsim.visuals {
                     tiltDecayer = 0;
                 }
 
-                let bbox = this.element.getBoundingClientRect();
-                let ax = (ev.clientX - bbox.width / 2) / (bbox.width / 3);
-                let ay = (ev.clientY - bbox.height / 2) / (bbox.height / 3);
+                const bbox = this.element.getBoundingClientRect();
+                const ax = (ev.clientX - bbox.width / 2) / (bbox.width / 3);
+                const ay = (ev.clientY - bbox.height / 2) / (bbox.height / 3);
 
-                let x = - Math.max(- 1023, Math.min(1023, Math.floor(ax * 1023)));
-                let y = Math.max(- 1023, Math.min(1023, Math.floor(ay * 1023)));
-                let z2 = 1023 * 1023 - x * x - y * y;
-                let z = Math.floor((z2 > 0 ? -1 : 1) * Math.sqrt(Math.abs(z2)));
+                const x = - Math.max(- 1023, Math.min(1023, Math.floor(ax * 1023)));
+                const y = - Math.max(- 1023, Math.min(1023, Math.floor(ay * 1023)));
+                const z2 = 1023 * 1023 - x * x - y * y;
+                const z = Math.floor((z2 > 0 ? -1 : 1) * Math.sqrt(Math.abs(z2)));
 
                 state.accelerometerState.accelerometer.update(x, y, z);
                 this.updateTilt();