Desplegué mi aplicación a Heroku. Es una aplicación node.js + express + socket.io y esta es lapackage.json expediente

{
  "name": "game_test",
  "author": "Ilya",
  "description": "A test app for our board game",
  "version": "0.0.1",
  "private": true,
  "scripts": {
    "start": "node app"
  },
  "dependencies": {
    "express": "3.0.6",
    "jade": "*",
    "socket.io" : "*"
  },
 "engines": {
      "node": "0.8.14"
  }
}

Este es el registro que obtengo:

heroku[router]: at=error code=H10 desc="App crashed" method=GET path=/ host=game-test-1.herokuapp.com fwd=37.26.146.185 dyno= queue= wait= connect= service= status=503 bytes=
heroku[router]: at=error code=H10 desc="App crashed" method=GET path=/favicon.ico host=game-test-1.herokuapp.com fwd=37.26.146.185 dyno= queue= wait= connect= service= status=503 bytes=

Qué significa eso?