Two devs. Building apps that actually work.

We are Marius Kieler and Phillip Eis. Two full-time developers with years of real-world experience shipping scalable, loved software.

No decks, no fluff. We design, build, and maintain products that people want to use.

CopenhagenEst. 2026

Work

CaloriSpy

Calorie tracking that reads your grocery receipts, so the food you already bought is already counted. Danish shops, Danish products, no diary to keep.

Netto København Ø18.08.26 17:42
RUGBRØD GROFT22,95
Rugbrød groft88 kcal
SKYR VANILJE14,50
Skyr vanilje148 kcal
KYLLINGEBRYST49,95
Kyllingebryst222 kcal
BÆREPOSE2,00
Not food

4 lines · 3 matched · 1 skipped

A line on a Netto receipt, recognised as a Danish product with numbers on it. That is the whole product, about 40 times a week.

Platform
React Native, Expo
Role
Design, app, backend, support inbox
Status
Live, and we run it
calorispy.com
Tuesday 18 Aug2 200
1 654
kcal left
  • Rugbrød groft2 slices176
  • Skyr vanilje1 pot148
  • Kyllingebryst180 g222
3 items from your Netto receipt

What we do

Whole products, not tickets.

Web apps & SaaS products

First screen to the billing that has to work on a Sunday night.

Mobile-friendly frontends

React Native and Expo, and web that behaves on a phone.

Backend systems that scale

Data models, queues and integrations, hosted in the EU and monitored.

Product design that stays out of the way

Drawn and built by the same hands, so nothing is lost in a handover.

How it starts

A few projects at a time, because the two people writing the code are the two people answering the mail.

01

A call, half an hour

You tell us what it is. We say whether we are the right two people, and we say so plainly if we are not.

02

A paid week to scope it

We draw the thing, agree what is in and out, and give you a fixed price for the build. The drawings are yours either way.

03

Two-week blocks

Something works at the end of every one. You see it running, not a status report.

The two of us

Marius Kieler

Backend, and the parser that turns a line on a Netto receipt into food with numbers on it.

kieler.dev

Phillip Eis

The apps people touch, and the settings screen that has its own theme because he insisted.

LinkedIn
  • No decks. You get something running instead.
  • The people who write the code answer the mail.
  • Hosted in the EU, and we keep an eye on it.
  • We do not take on what we cannot maintain.

Have something you want to build?

hello@insidestudio.devDanish or English. One of us answers.