Error page
If your app is not responding, Hatchbox will render a default error page. 

To customize the error page HTML, you can edit the html template found here:

/home/deploy/.hatchbox/templates/error.html

Maintenance Mode page
If your app is in maintenance mode, Hatchbox will render a default page.
 
To customize the maintenance mode page HTML, you can edit the html template found here:

/home/deploy/.hatchbox/templates/maintenance.html

Note: This will work for all apps on your server.

If you would like to customize the maintenance mode page for each individual app, we recommend using the turnout gem.  It's pretty great because it can also allow you to still view the app as the developer during maintenance mode.

https://github.com/biola/turnout