I'm part of the core Nanobox team (https://nanobox.io). Members of our team were instrumental in introducing releases in Elixir and helped to lay the foundation for exrm.
Elixir deploys are currently functional, but we're working with the Elixir community to really fine-tune the process (including hot-code-reloads).
DigitalOcean has been supported for a few months now. AWS support was just released yesterday.
Nanobox is a portable "micro" PaaS, we don't provide servers, we integrate with your host of choice and provision servers for you. The cost and number of servers your application needs/uses is between you and your host (AWS, DO, etc).
The $99 you pay to Nanobox is for the use of the Nanobox Dashboard to manage your application on your host (Nanobox Desktop is free).
Elixir deploys are currently functional, but we're working with the Elixir community to really fine-tune the process (including hot-code-reloads).
DigitalOcean has been supported for a few months now. AWS support was just released yesterday.