Solo developer · New Zealand

I make small, honest software that solves one real problem beautifully, and then gets out of your way.

No ads, no tracking, no overpriced subscriptions. Some of these are yours to buy once and keep; others run on servers, so they cost what they cost to run.

See what I'm building

Work

Things I've made

Flagship

Plotstead

Every property has a hundred things to remember: which trench the power cable runs down, when the WOF is due, who fixed the roof and what they charged. Type your address and the boundary arrives from LINZ; the buildings, pipes and cables go onto the aerial photo with their manuals, costs and reminders attached. Rentals and Airbnbs get the money side too, and it exports ready for the accountant at tax time.

A map, not a list Works offline NZ compliance dates Share part of the place

Visit Plotstead Start free

One property free, forever. No card.

Web Live Android In testing iPhone & iPad Soon Windows Soon

A property's map in Plotstead: pins, pipe runs and areas on an aerial photo

Tideline NZ

A rock-solid offline tide app for Kiwi boaties, anglers, surfers, kayakers and divers. It gives you trustworthy tide predictions for 310+ spots around the country. Once it's on your phone it works offline, exactly what you want when you're at a remote boat ramp with zero bars of signal. Now on iPhone and iPad, as well as Android and Windows.

Offline No ads Bite times Launch window

Visit Tideline NZ App Store New Google Play Windows Store

Fine Day

Answers one deceptively hard question: when can I hang the washing out? Fine Day scans 14 days of hour-by-hour rain forecasts to find your dry windows. Handy for washing lines, lawn mowing, painting, concrete pours, and anything else the weather keeps interrupting.

Free 14-day forecast No ads

On a Home Assistant dashboard

Visit Fine Day Google Play

Fine Day on a phone: today's answer for Northcote, Auckland is Yes, with an hour-by-hour chart of wet morning and good afternoon hours

MousePhaser

Two computers on one desk, two mice, and a hand that keeps reaching for the wrong one. MousePhaser gives your Windows PCs one mouse between them: push the pointer off the edge of the screen and it carries on across the laptop beside you, clicks, drags and wheel included, then comes back the same way. The computers find each other, a passphrase keeps everyone else out, and you arrange them the way the old display settings arranged monitors: drag the laptop onto the side of the desk it sits on.

One mouse, every PC Passphrase paired Finds the others itself No ads, no account

Visit MousePhaser Windows Store New

$4.90 once, and it covers every PC on your Microsoft account: install it on the others from the Store with the same sign-in, nothing to pay twice. Windows 10 and 11.

MousePhaser on Windows: the Pairing card, and the arrangement picture with a laptop placed to the left of this computer

More in the works

There are a few more ideas quietly simmering away. They'll show up here once they're properly baked and genuinely worth your time.

Websites for hire

I also build websites for other people

Same principle as everything else here: a site your business actually owns, built lean so it loads fast, and roughly $100 a year to run instead of the $700 a site builder charges you to rent your own front door.

Anywhere in New Zealand, and you can either hand it to me to look after or take the keys and run it yourself.

Two recent ones: Mahurangi River Retreat, an eco-luxury tiny house to stay in near Warkworth, and Coleman's Mobile Car Valet, a mobile car detailer who comes to you in Auckland.

What that involves

The Mahurangi River Retreat website: a tiny house lit at dusk under the words Escape the city and step into total seclusion

Home automation

I also do custom home automation

Lights, heating, blinds, gates, cameras, a fish tank that looks after itself, a circuit-by-circuit power monitor in the switchboard that shows what's eating the bill, and the odd thing nobody makes an app for. All of it tied together on Home Assistant, so it runs in your house rather than on somebody's cloud. Built around how you actually live in the place, and handed over with the keys like everything else here.

Fine Day already sits on a Home Assistant dashboard, so the next dry window is on the wall by the back door.

Ask about it

Built on Home Assistant

A Home Assistant weather dashboard: the week's forecast, the living room temperature over the last 24 hours, and Fine Day's card saying No, not today

About the developer

Hello, I'm James Sumner

I'm an independent software developer based in Auckland, New Zealand. SumnerD / Sumner Software Development is a one-person operation, just me. The name comes from my nickname growing up, sumnerd (some nerd).

Honestly? I got tired of everyday apps crammed with ads and subscriptions that quietly nibble away at your bank account. So I set out to build the opposite: no ads, no tracking, no overpriced subscriptions, and no charging you monthly for something that runs perfectly well standalone.

Tideline NZ, Fine Day and MousePhaser are the first of them, all built and maintained here in New Zealand. Buy once or use free, and they're yours. The same thinking goes into the websites and home automation I build for other people: lean, owned outright, and handed over with the keys.

Some things genuinely do need a server behind them. Plotstead is the first of those: it syncs between your devices and keeps your records safe if your phone goes in the drink, so there's a subscription to cover what it costs to run, and a free tier that isn't a trial waiting to run out. What won't change is the rest of it. If that's the sort of software you've been missing, you're in the right place.

Get in touch

Say hello

Got an idea worth building, a bit of feedback on an app, a website you need built, or just want to say hello? I'd genuinely love to hear from you.

hello@sumnerd.co.nz