Android

You can easily run NodeJS apps on an Android phone with Termux

Termux is an Android terminal emulator and Linux environment app that works directly with no rooting or setup required. A minimal base system is installed automatically - additional packages are available using the APT package manager.

APK: https://f-droid.org/en/packages/com.termux/

Setup

Here is a simple gun relay server.

Start a new repo:

// server.js

;(function(){
  var gun = require('gun/examples/http');
  if(!gun.back){ return } // http example auto spawns subprocess

  var fs = require('fs');
  var server = gun.back('opt.web');
  var route = server.route = {}

  fs.readdir('./route', function(err, dir){
      if(err || !dir){ return }
      dir.forEach(function(file){
          if(!file){ return }
          route[file.split('.')[0]] = require('./route/'+file);
      });
  });
 
// with this line you can type a message on http://localhost:8765/basic/paste.html and check if the server works.
  gun.get('test').on(data => console.log(data))

}());

-npm gun -npm start

Make your mobile gun server available from the outside.

https://www.noip.com/integrate/request (free user account neccessary)

Use cases

• i use it to collect data 24/7 with my mobile from a subscribe form, which is on my static website on a CDN. by by classic back-end!
• thinking about a gun emailserver on my mobile. by by classic email provider! (take a look on Cloudflare Email Routing https://developers.cloudflare.com/email-routing/)

feel free to add more...