The 2G network died. The gate didn't have to.

How it started: the gate that stopped working

The gate at our place ran on a 2G GSM module for years. You called its SIM number, it pulsed a relay, the gate opened. No app, no internet, no fuss. For something installed in a weatherproof box on a fence post and forgotten, it was perfect — until it wasn't.

When the carrier started phasing out 2G, our gate started missing calls. First intermittently, then constantly. The fix was obvious: replace the hardware with a 4G-capable module. The hardware part was easy — there are dozens of options on the market.

The software part was where everything fell apart.

What I went looking for

I wanted a clean companion app that would let me add a number, set a time-limited code for a cleaner, and see a log of who opened the gate. The kind of thing you'd expect for a piece of hardware that costs real money in 2026.

What I found instead:

• Manufacturer apps that only worked with their one specific model, required a cloud account, ran in broken Chinese, and shipped with ads.
• A handful of third-party apps with 2-star reviews, English-only menus, and no support for the most common protocols at the same time.
• A pile of forum threads where people typed raw SMS commands like 1234#TEL+31612345678#001# into their phone from memory because nothing better existed.

That last option is what I ended up doing for about three weeks. I kept a sticky note of the commands. Every time I needed to add a number I had to find the note. Every time I made a typo I got "Password Error" with no clue why. It was 2026 and I was operating my front gate like it was 2005.

Why I built it instead of waiting

I'm a software engineer. The first version of GateOpener was a one-screen Android app for my own gate — a single button that called the SIM and a form that wrapped the add-user SMS command. It took a weekend.

Then I showed it to a friend with the same module, and they asked for a copy. Then I posted it in a forum thread, and three people from three different countries with three different module brands asked if it would work with theirs. I went looking at the SMS protocols and realised that two protocol families — RTU5024 and Callny — cover roughly 85% of every GSM gate module sold worldwide. If one app spoke both, it would work for almost everyone.

So I rebuilt it properly. I added support for both protocols. I translated it into sixteen languages, because most competing apps were English only and the people stuck typing SMS commands aren't all in English-speaking countries. I added a home screen widget so the gate opens in two seconds without launching the app. I added time-limited guest access for short-term rentals. I encrypted everything that needed encrypting and shipped it with no accounts, no cloud, no tracking. And I priced it at €4.99 one-time — because the whole point was to fix a small annoying problem, not to extract a subscription out of people who already paid for hardware.

What I promise

• No accounts. The app never asks you to sign up. There's no cloud service to leak.
• No servers. GateOpener talks to your gate module directly via SMS and phone calls. Nothing leaves your phone.
• No tracking. No analytics, no advertising, no third-party SDKs that report your behaviour.
• One-time purchase. €4.99 once. No subscriptions. Free updates for the life of the app.
• Open hardware request list. If your module isn't supported, I add it — if you can share the SMS command documentation.
• A real person on the other end. Hardware support requests go to my inbox, not a queue. Replies come from me.

Where I write everything from

I'm a software engineer based in the Netherlands. I publish the app under my company, Mandoloran, but everything you read on this site — every blog post, every hardware page, every SMS command reference — is written by me, tested against real hardware on my own gate, and dated so you can see when it was last reviewed.

If a command on gate-opener.app/blog doesn't work for you, I want to hear about it. I'd rather fix a wrong command than have you stuck at your gate at 11pm. Email me at [email protected].

What I've built so far

• Native Android app supporting the RTU5024 and Callny G202 / G203 protocol families — roughly 85% of GSM gate openers sold worldwide.
• Sixteen-language localisation from launch day.
• Home screen widget that opens the gate in under two seconds without launching the app.
• Temporary access scheduling with automatic expiry, for cleaners and Airbnb guests.
• Per-gate activity log so you can see who opened the gate and when.
• A growing reference site at gate-opener.app with setup guides, troubleshooting articles, manuals, and the full SMS command reference for every supported module.

Editorial standards

Every post on this site is written by me and tested against real hardware. When I review or update an article, I bump the Last reviewed date so you know how fresh the information is. Sources for SMS commands and hardware specifications are linked at the bottom of each article. Corrections are welcome — they reach me directly.

How to reach me

• Email: [email protected]
• Hardware support requests: /request-hardware/
• Play Store listing: GateOpener on Google Play