diff --git a/android.sh b/android.sh
new file mode 100755
index 0000000..96997e7
--- /dev/null
+++ b/android.sh
@@ -0,0 +1,6 @@
+#!/usr/bin/env bash
+
+# build it
+./lib/bs/native/builder.native
+cp assets/* android/app/src/main/assets/
+cd android && ./gradlew installDebug
\ No newline at end of file
diff --git a/assets/flappy.fnt b/assets/flappy.fnt
new file mode 100644
index 0000000..3d2e2aa
--- /dev/null
+++ b/assets/flappy.fnt
@@ -0,0 +1,15 @@
+info face=flappy size=32 bold=0 italic=0 charset= unicode= stretchH=100 smooth=1 aa=1 padding=3,3,3,3 spacing=0,0 outline=0
+common lineHeight=36 base=25 scaleW=512 scaleH=512 pages=1 packed=0
+page id=0 file="flappy.png"
+chars count=10
+char id=48 x=494 y=59 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=49 x=135 y=454 width=12 height=20 xoffset=2 yoffset=0 xadvance=14 page=0 chnl=15
+char id=50 x=291 y=159 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=51 x=305 y=159 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=52 x=319 y=159 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=53 x=333 y=159 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=54 x=291 y=183 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=55 x=305 y=183 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=56 x=319 y=183 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+char id=57 x=333 y=183 width=14 height=20 xoffset=0 yoffset=0 xadvance=14 page=0 chnl=15
+kernings count=0
diff --git a/builder/Builder.re b/builder/Builder.re
index 52015ec..c3d0fca 100644
--- a/builder/Builder.re
+++ b/builder/Builder.re
@@ -168,13 +168,15 @@ let compile = config => {
 compile({
   name: "gravitron",
   shared: true,
-  mainFile: "./src/prod.re",
+  /* mainFile: "./src/prod.re", */
+  mainFile: "./flap/FlappyBird.re",
   cOpts: "-fno-omit-frame-pointer -O3 -fPIC -llog -landroid -lGLESv3 -lEGL",
   mlOpts: "-runtime-variant _pic",
   dependencyDirs: ["./reasongl-interface/src", "./reasongl-android/src", "./reprocessing/src"],
   buildDir: "_build",
   env: "BSB_BACKEND=native-android",
-  outDir: "./",
+
+  outDir: "./android/app/src/main/jniLibs/armeabi-v7a/",
   ppx: ["./reasongl-android/matchenv.ppx"],
   ocamlDir: "~/.opam/4.04.0-android32/android-sysroot",
   refmt: "~/.opam/4.04.2/bin/refmt",
diff --git a/flap/FlappyBird.re b/flap/FlappyBird.re
new file mode 100644
index 0000000..731756a
--- /dev/null
+++ b/flap/FlappyBird.re
@@ -0,0 +1,280 @@
+open Reprocessing;
+
+let jumpForce = (-260.);
+
+let speed = 175.;
+
+let pipeWidth = 50.;
+
+let halfGap = 70.;
+
+let birdSize = 20.;
+
+let gravity = 800.;
+
+let birdX = 50.;
+
+let defaultBirdY = 50.;
+
+let pipeHeight = 350.;
+
+let floorY = 500.;
+
+type runningT =
+  | Running
+  | Dead
+  | Restart;
+
+type stateT = {
+  birdY: float,
+  birdVY: float,
+  pipes: list((float, float)),
+  xOffset: float,
+  running: runningT,
+  image: imageT,
+  logo: imageT,
+  font: fontT,
+  score: int
+};
+
+let setup = (env) => {
+  Env.size(~width=400, ~height=640, env);
+  {
+    birdY: defaultBirdY,
+    birdVY: 0.,
+    pipes: [(200., 100.), (400., 100.), (600., 100.), (800., 100.)],
+    xOffset: 0.,
+    running: Running,
+    image: Draw.loadImage(~filename="flappy.png", ~isPixel=true, env),
+    logo: Draw.loadImage(~filename="reason-logo.png", env),
+    font: Draw.loadFont(~filename="flappy.fnt", ~isPixel=true, env),
+    score: 0
+  }
+};
+
+let generatePipe = (x) => (
+  x +. Utils.randomf(~min=200., ~max=300.),
+  Utils.randomf(~min=50. +. halfGap, ~max=floorY -. 50. -. halfGap)
+);
+
+let generateNewPipes = ({pipes, xOffset}) =>
+  List.map(
+    ((x, _) as pipe) =>
+      if (x -. xOffset +. pipeWidth <= 0.) {
+        let newX = List.fold_left((maxX, (x, _)) => max(maxX, x), 0., pipes);
+        generatePipe(newX)
+      } else {
+        pipe
+      },
+    pipes
+  );
+
+let drawBird = (state, env) => {
+  Draw.pushMatrix(env);
+  Draw.translate(~x=birdX, ~y=state.birdY -. 2., env);
+  let low1 = (-200.);
+  Draw.rotate(
+    Utils.remapf(~value=state.birdVY, ~low1, ~high1=1200., ~low2=(-0.5), ~high2=1.5),
+    env
+  );
+  Draw.translate(~x=birdSize *. (-1.), ~y=birdSize *. (-1.), env);
+  switch (int_of_float(state.xOffset /. 20.) mod 3) {
+  | 0 =>
+    Draw.subImage(
+      state.image,
+      ~pos=(0, 0),
+      ~width=int_of_float(birdSize) * 2 + 4,
+      ~height=int_of_float(birdSize) * 2 + 4,
+      ~texPos=(115, 378),
+      ~texWidth=17,
+      ~texHeight=17,
+      env
+    )
+  | 1 =>
+    Draw.subImage(
+      state.image,
+      ~pos=(0, 0),
+      ~width=int_of_float(birdSize) * 2 + 4,
+      ~height=int_of_float(birdSize) * 2 + 4,
+      ~texPos=(115, 404),
+      ~texWidth=17,
+      ~texHeight=17,
+      env
+    )
+  | 2 =>
+    Draw.subImage(
+      state.image,
+      ~pos=(0, 0),
+      ~width=int_of_float(birdSize) * 2 + 4,
+      ~height=int_of_float(birdSize) * 2 + 4,
+      ~texPos=(115, 430),
+      ~texWidth=17,
+      ~texHeight=17,
+      env
+    )
+  | _ => assert false
+  };
+  Draw.popMatrix(env)
+};
+
+let drawPipes = ({xOffset, pipes, image}, env) =>
+  List.iter(
+    ((x, y)) => {
+      let height = - int_of_float(pipeHeight);
+      Draw.subImage(
+        image,
+        ~pos=(int_of_float(x -. xOffset), int_of_float(y -. halfGap)),
+        ~width=int_of_float(pipeWidth),
+        ~height,
+        ~texPos=(0, 323),
+        ~texWidth=26,
+        ~texHeight=160,
+        env
+      );
+      Draw.subImage(
+        image,
+        ~pos=(int_of_float(x -. xOffset), int_of_float(y +. halfGap)),
+        ~width=int_of_float(pipeWidth),
+        ~height=int_of_float(pipeHeight),
+        ~texPos=(0, 323),
+        ~texWidth=26,
+        ~texHeight=160,
+        env
+      )
+    },
+    pipes
+  );
+
+let drawTiledThing = ({image}, ~texPos, ~texWidth, ~texHeight, ~xOffset, ~y, ~height, env) => {
+  let width = Env.width(env);
+  Draw.subImage(
+    image,
+    ~pos=(int_of_float(-. xOffset) mod width, int_of_float(y)),
+    ~width,
+    ~height,
+    ~texPos,
+    ~texWidth,
+    ~texHeight,
+    env
+  );
+  Draw.subImage(
+    image,
+    ~pos=(int_of_float(-. xOffset) mod width + width, int_of_float(y)),
+    ~width,
+    ~height,
+    ~texPos,
+    ~texWidth,
+    ~texHeight,
+    env
+  )
+};
+
+let draw = ({font, score, image, birdY, birdVY, pipes, xOffset, running} as state, env) => {
+  let userInput =
+    switch Reasongl.Gl.target {
+    | "native-ios" => Env.mousePressed(env)
+    | "native-android" => Env.mousePressed(env)
+    | _ => Env.keyPressed(Space, env)
+    };
+  drawTiledThing(
+    state,
+    ~texPos=(146, 0),
+    ~texWidth=144,
+    ~texHeight=256,
+    ~xOffset=xOffset /. 2.,
+    ~y=0.,
+    ~height=Env.height(env),
+    env
+  );
+  drawPipes(state, env);
+  drawTiledThing(
+    state,
+    ~texPos=(292, 0),
+    ~texWidth=168,
+    ~texHeight=56,
+    ~xOffset,
+    ~y=floorY,
+    ~height=Env.height(env) - int_of_float(floorY),
+    env
+  );
+  Draw.image(state.logo, ~pos=(10, Env.height(env) - 50), ~width=40, ~height=40, env);
+  drawBird(state, env);
+  Draw.pushMatrix(env);
+  Draw.translate(~x=170., ~y=90., env);
+  Draw.scale(~x=3., ~y=3., env);
+  Draw.text(~font, ~body=string_of_int(score), ~pos=(0, 0), env);
+  Draw.popMatrix(env);
+  if (running != Running) {
+    Draw.subImage(
+      image,
+      ~pos=(60, 200),
+      ~width=291,
+      ~height=63,
+      ~texPos=(395, 59),
+      ~texWidth=97,
+      ~texHeight=21,
+      env
+    )
+  };
+  let collided =
+    List.exists(
+      ((x, y)) =>
+        Utils.intersectRectCircle(
+          ~rectPos=(x -. xOffset, 0.),
+          ~rectW=pipeWidth,
+          ~rectH=y -. halfGap,
+          ~circlePos=(birdX, birdY),
+          ~circleRad=birdSize
+        )
+        || Utils.intersectRectCircle(
+             ~rectPos=(x -. xOffset, y +. halfGap),
+             ~rectW=pipeWidth,
+             ~rectH=float_of_int(Env.height(env)),
+             ~circlePos=(birdX, birdY),
+             ~circleRad=birdSize
+           ),
+      pipes
+    );
+  let pipes = generateNewPipes(state);
+  let hitFloor = birdY >= floorY -. birdSize;
+  let deltaTime = Env.deltaTime(env);
+  switch running {
+  | Running => {
+      ...state,
+      pipes,
+      birdY: max(min(birdY +. birdVY *. deltaTime, floorY -. birdSize), birdSize),
+      birdVY: userInput || collided ? jumpForce : birdVY +. gravity *. deltaTime,
+      xOffset: xOffset +. speed *. deltaTime,
+      running: collided || hitFloor ? Dead : Running,
+      score:
+        List.exists(
+          ((x, _)) => birdX +. xOffset <= x && birdX +. xOffset +. speed *. deltaTime > x,
+          pipes
+        ) ?
+          score + 1 : score
+    }
+  | Dead => {
+      ...state,
+      pipes,
+      birdY: max(min(birdY +. birdVY *. deltaTime, floorY -. birdSize), birdSize),
+      birdVY: birdVY +. gravity *. deltaTime,
+      running: hitFloor ? Restart : Dead
+    }
+  | Restart =>
+    if (userInput) {
+      {
+        ...state,
+        pipes: [generatePipe(200.), generatePipe(400.), generatePipe(600.), generatePipe(800.)],
+        birdY: defaultBirdY,
+        birdVY: 0.,
+        xOffset: 0.,
+        running: Running,
+        score: 0
+      }
+    } else {
+      state
+    }
+  }
+};
+
+run(~setup, ~draw, ());
\ No newline at end of file