I'm curious, what don't you like about ngrok? Is it just that it's a paid service? You do need a server somewhere to forward connections and that normally costs money to run
The source for the backend portion is also available, https://github.com/localtunnel/server. Going to set it up shortly on my own personal box, and if it works smoothly I'll be able to present it as a self-hosted alternative to my employer.
It's good to ensure survival and utility of cool things such that Tragedy of the Commons doesn't spoil them.