Founder of EnvKey here - thanks for the mention!
EnvKey takes a minimalistic and developer-friendly approach to managing configuration and secrets. It keeps secrets safe while also making it extremely easy to make them available wherever you need them, edit them, and grant/revoke access.
With EnvKey, you can just set a single environment variable (ENVKEY=...) and have any dev machine or server fully configured in seconds. It's a lot simpler and (imho) more pleasant to work with than alternatives.
I'm happy to answer questions about it here if anyone has them!