routes map and correct path

Try:

<% form_for @app, @user do |f| %>

Where your controller should look like

def new
  @app = App.find(params[:app_id])
  @user = User.new
  @user.app_id = params[:app_id]
end

Sorry, it should be:

<% form_for [@app, @user] do |f| %>

Erol Fornoles wrote: