/myapplication
  /__init__.py
  /views
    /__init__.py
    /admin.py
    /frontend.py

/myapplication
  /__init__.py
  /app.py
  /views
    /__init__.py
    /admin.py
    /blog.py

# admin.py
from flask import Module
admin = Module(__name__)
@admin.route('/')
def index():
  return "This is admin page!"
@admin.route('/profile')
def profile():
  return "This is profile page."

# blog.py
from flask import Module
blog = Module(__name__)
@blog.route('/')
def index():
  return "This is my blog!"
@blog.route('/article/<int:id>')
def article(id):
  return "The article id is %d." % id

# app.py
from flask import Flask
from views.admin import admin
from views.blog import blog
app = Flask(__name__)
@app.route('/')
def index():
  return "This is my app."
app.register_module(blog, url_prefix='/blog')
app.register_module(admin, url_prefix='/admin')
if __name__ == '__main__':
  from werkzeug.serving import run_simple
  run_simple('localhost', 5000, app)

def register_module(self, module, **options):
  """Registers a module with this application. The keyword argument
  of this function are the same as the ones for the constructor of the
  :class:`Module` class and will override the values of the module if
  provided.
  """
  options.setdefault('url_prefix', module.url_prefix)
  state = _ModuleSetupState(self, **options)
  for func in module._register_events:
    func(state)

>>> app.url_map
Map([<Rule '/admin/profile' (HEAD, GET) -> admin.profile>,
   <Rule '/admin/' (HEAD, GET) -> admin.index>,
   <Rule '/blog/' (HEAD, GET) -> blog.index>,
   <Rule '/' (HEAD, GET) -> index>,
   <Rule '/blog/article/<id>' (HEAD, GET) -> blog.article>,
   <Rule '/static/<filename>' (HEAD, GET) -> static>]
  )
>>> app.url_map._rules_by_endpoint
{'admin.index': [<Rule '/admin/' (HEAD, GET) -> admin.index>],
 'admin.profile': [<Rule '/admin/profile' (HEAD, GET) -> admin.profile>],
 'blog.article': [<Rule '/blog/article/<id>' (HEAD, GET) -> blog.article>],
 'blog.index': [<Rule '/blog/' (HEAD, GET) -> blog.index>],
 'index': [<Rule '/' (HEAD, GET) -> index>],
 'static': [<Rule '/static/<filename>' (HEAD, GET) -> static>]
}
>>> app.view_functions
{'admin.index': <function views.admin.index>,
 'admin.profile': <function views.admin.profile>,
 'blog.article': <function views.blog.article>,
 'blog.index': <function views.blog.index>,
 'index': <function __main__.index>
}