It should be ok as they even mention using it for exposing services like RDP and I've seen some people using it for game servers, but you might want to get a paid plan since your endpoint changes every time you fire up ngrok and it's annoying. You can also check the open source alternative if you feel like it won't be a problem for you. - Source: Reddit / 18 days ago
Source code: https://bitbucket.org/ValdikSS/dropbear-sshj/ After I made the PoC modifications and setup the server on SSH-J.com, I found functionally better and mature project called sish. Https://github.com/antoniomika/sish. - Source: Reddit / 18 days ago
ngrok - ngrok enables secure introspectable tunnels to localhost webhook development tool and debugging tool.
browserling - Live interactive cross-browser testing from your browser.
Portmap.io - Expose your local PC to Internet from behind firewall and without real IP address
BrowserStack - Test your website for cross browser compatibility on real browsers. Instant access to multiple desktop and mobile browsers. Get Free Trial.
Packetriot - Secure and Instant hosting on any network.
Choosy - Choosy opens links in different browsers as specified, according to rules, set by the user.