Application fails to run on Heroku - angularjs

Question

I have NodeJs application with yeoman, grunt, bower installed. I generatedm angularjs app using yeomen. Local version of application runs with no problem by typing grunt serve. Moreover application was successfully deployed to Heroku by grunt deploy link. When trying to access application on heroku it shows:
Application Error An error occurred in the application and your page
could not be served. Please try again in a few moments.
If you are the application owner, check your logs for details.
In application log (Heroku dashboard > Activity):
Deployed
Build succeeded
-----> Node.js app detected
-----> Reading application state
package.json...
build directory...
cache directory...
environment variables...
Node engine: >=0.10.0
Npm engine: unspecified
Start mechanism: Procfile
node_modules source: package.json
node_modules cached: true
NPM_CONFIG_PRODUCTION=true
NODE_MODULES_CACHE=true
-----> Installing binaries
Resolving node version >=0.10.0 via semver.io...
Downloading and installing node 0.10.35...
Using default npm version: 1.4.28
-----> Building dependencies
Restoring node modules from cache
Pruning unused dependencies
npm WARN package.json nodejsw3#0.0.0 No repository field.
Installing any new modules
npm WARN package.json nodejsw3#0.0.0 No repository field.
-----> Checking startup method
Found Procfile
-----> Finalizing build
Creating runtime environment
Exporting binary paths
Cleaning npm artifacts
Cleaning previous cache
Caching results for future builds
-----> Build succeeded!
nodejsw3#0.0.0 /tmp/build_9b26539892553ae79f16e539e2f083e0
????????? (empty)
WARNING: Avoid semver ranges starting with '>' in engines.node
https://devcenter.heroku.com/articles/nodejs-support#specifying-a-node-js-version
-----> Discovering process types
Procfile declares types -> web
-----> Compressing... done, 6.8MB
-----> Launching... done, v9
https://myapp.herokuapp.com/ deployed to Heroku
Project structure:
Log
2015-02-07T17:49:56.504866+00:00 heroku[router]: at=error code=H10 desc="App cra
shed" method=GET path="/" host=myapp.herokuapp.com request_id=257d316d-98
d1-4d21-a170-7c27e42b907e fwd="10.10.10.11" dyno= connect= service= status=503
bytes=
2015-02-07T17:49:57.762152+00:00 heroku[router]: at=error code=H10 desc="App cra
shed" method=GET path="/favicon.ico" host=myapp.herokuapp.com request_id=
f109ba40-e921-486a-a79a-7a7d842705a7 fwd="10.10.10.11" dyno= connect= service=
status=503 bytes=
2015-02-07T17:53:40.155437+00:00 heroku[router]: at=error code=H10 desc="App cra
shed" method=GET path="/" host=myapp.herokuapp.com request_id=7e0e784c-0e
76-48b1-ad3e-bbf74b400e31 fwd="10.10.10.11" dyno= connect= service= status=503
bytes=
2015-02-07T17:53:41.454002+00:00 heroku[router]: at=error code=H10 desc="App cra
shed" method=GET path="/favicon.ico" host=myapp.herokuapp.com request_id=
4d56eacf-5515-48e4-9b5d-34ccc4c4457e fwd="10.10.10.11" dyno= connect= service=
status=503 bytes=
2015-02-07T17:54:20.109125+00:00 heroku[router]: at=error code=H10 desc="App cra
shed" method=GET path="/" host=myapp.herokuapp.com request_id=b244e431-81
d6-4f82-a0e0-1e845a45a449 fwd="10.10.10.11" dyno= connect= service= status=503
bytes=
2015-02-07T17:54:21.286203+00:00 heroku[router]: at=error code=H10 desc="App cra
shed" method=GET path="/favicon.ico" host=myapp.herokuapp.com request_id=
e2c7d762-a88c-49f6-a15b-e1768e7310d5 fwd="10.10.10.11" dyno= connect= service=
status=503 bytes=
2015-02-07T17:57:14.924093+00:00 heroku[web.1]: State changed from crashed to st
arting
2015-02-07T17:57:16.809601+00:00 heroku[web.1]: Starting process with command `n
ode index.js`
2015-02-07T17:57:18.731681+00:00 app[web.1]: module.js:340
2015-02-07T17:57:18.736235+00:00 app[web.1]: at Function.Module._resolveFile
name (module.js:338:15)
2015-02-07T17:57:18.736237+00:00 app[web.1]: at Function.Module._load (modul
e.js:280:25)
2015-02-07T17:57:18.736241+00:00 app[web.1]: at require (module.js:380:17)
2015-02-07T17:57:18.736243+00:00 app[web.1]: at Object.<anonymous> (/app/ind
ex.js:1:77)
2015-02-07T17:57:18.732015+00:00 app[web.1]: throw err;
2015-02-07T17:57:18.736244+00:00 app[web.1]: at Module._compile (module.js:4
56:26)
2015-02-07T17:57:18.731200+00:00 app[web.1]:
2015-02-07T17:57:18.732021+00:00 app[web.1]: ^
2015-02-07T17:57:18.736232+00:00 app[web.1]: Error: Cannot find module 'express'
2015-02-07T17:57:18.736239+00:00 app[web.1]: at Module.require (module.js:36
4:17)
2015-02-07T17:57:18.736246+00:00 app[web.1]: at Object.Module._extensions..j
s (module.js:474:10)
2015-02-07T17:57:18.736247+00:00 app[web.1]: at Module.load (module.js:356:3
2)
2015-02-07T17:57:18.736249+00:00 app[web.1]: at Function.Module._load (modul
e.js:312:12)
2015-02-07T17:57:18.736251+00:00 app[web.1]: at Function.Module.runMain (mod
ule.js:497:10)
2015-02-07T17:57:19.580364+00:00 heroku[web.1]: Process exited with status 8
2015-02-07T17:57:19.592340+00:00 heroku[web.1]: State changed from starting to c
rashed