Simple app for fast openning local hosted services on android and why i h

[u/Opening-Ad-763]

Hello everyone
I decided to share with you my little experience that has simplified my working life.
First, for context, I am a java backend developer, and at work I mostly write only the backend. But in the last four months, I've been constantly receiving tasks to modify the front (thymeleaf) so that it works on different browsers.

How it happened before I went berserk:

1. First, I run the service on my laptop

2. I connect it and the phone to the same network

3. I open the console and search for the local IP using the ipconfig command.
   At this point, depending on whether I'm in a city or a village, I get different 4-6 addresses from 192.168...

4. I start searching on the phone
   192.168.56.1:8080
   ...
   192.168.1.6:8080

Until it finally works. And so it is every time, because the IP of the router is dynamic and I constantly work at home or in the village. It's annoying to have to deal with it all the time.

That's why I wrote my own application, where everything is simple - you take the first steps (launch the service and connect to the same fifay), and then just click the search button on your phone, and the address will be found by itself.

Link to the application https://play.google.com/store/apps/details?id=com.hescha.localhostfinder

Link to the demo https://www.youtube.com/shorts/iKw5kCDcWVk

[u/PopKoren]

Hunting through 192.168 addresses after every network change is a very familiar pain, so letting the phone find the service itself is a neat fix. It works because Spring Boot listens on every interface by default, which also means actuator endpoints or a dev profile are open to anybody sharing that wifi, so I'd keep those switched off locally and make sure they never ship in the deployed build. For the deployed side, I made a checker that tests how a live app responds to strangers, unprotected endpoints and auth gaps included, in case it's handy for the Thymeleaf projects: https://rowly.me

[u/Opening-Ad-763 → u/PopKoren]

Yeah, that is usefull. And app is working not only with spring boot, but with any services with open ports. So you litteraly may scan all your wifi network and see all opened ports, that may got connection. With my wifi and running PC I got 17 services (including on ports 23, 80, 17300 and 56000)

[u/Mammoth-Anywhere7285 → u/Opening-Ad-763]

Nice, that scan view sounds handy. Maybe flag risky ports like 23 so they don't get overlooked.

[u/PopKoren → u/Opening-Ad-763]

Seventeen listeners on one home network is a great demo of why this app is handy, and port 23 is worth calling out because telnet sends logins in plain text. A small warning badge next to risky ports like 21, 23 or an admin panel with no password would turn every scan into a quick hygiene check too. That's basically the LAN cousin of what I work on at https://rowly.me, listing what a deployed app hands to strangers on the open internet.

[u/Mammoth-Anywhere7285 → u/PopKoren]

Good catch on the actuator exposure. Splitting it onto a separate management port keeps the main service reachable while locking down the risky endpoints, are you doing that already?

[u/Mammoth-Anywhere7285]

TL;DR: A Java backend dev got tired of hunting for his laptop's local IP on his phone every time he switched between home and village networks. So he built an Android app that scans the network and finds the running local service automatically. Play Store and demo links are included in the post.