Projects
Client work is most of what I do, but building and running something of my own keeps the advice honest. You find out what shipping actually costs when the store listing, the privacy policy and the support address are yours.
go poschte
An AI shopping list for households in Switzerland, built on Google's Gemini. Ask it for a product, a dish like "lasagne for four" or a question, and it answers with what to buy, written in Swiss German and grouped by the aisles of the shop you are standing in. The family shares one list, and it keeps working with no signal.
Hue Daylight
Switches Philips Hue lights on when clouds make the day too dark, and off when it clears, using MeteoSwiss's forecast in Switzerland. Sunrise, sunset and bedtime stay with the Hue app.
Rogeha Capture
Screenshots for email, tickets and chat: capture a window, a region or a scrolling page, mark it up and paste it. Small on purpose, made to work on a laptop screen, and offline.
Rogeha Deutsch C1
German from B2 to C1: exercises an AI writes for you and grades by their goal, not by one fixed answer, with each mistake explained in German or English. Dictate your answers, have them read aloud, and let spaced repetition bring back what you got wrong.
Rogeha Scene
A video or a folder of photos turned into a 3D scene you can walk around in: Gaussian splatting or triangles, trained on a graphics card rented by the minute, with the price shown before anything is rented.
Why this is on a consultancy site
Each app is small on purpose. Between them they cover most of what a software product needs on its way to people: two platforms, two app stores, AI from several providers, speech, a connected device, and the testing and paperwork that let a release go out with confidence. What makes them worth showing is not the feature lists but the full path behind each one.
All the way through the store
A complete Google Play release for go poschte: signing keys, data safety declarations, a privacy policy, in-app account deletion, store assets. Rogeha Capture passed Microsoft Store certification and moved from 1.x to 2.0 under the same identity, so it updated in place. Rogeha Deutsch C1 followed it into the Store.
AI that holds up
go poschte runs on Google's Gemini, with real fallbacks for when the model is slow or wrong. Rogeha Deutsch C1 talks to Claude, OpenAI, Gemini or any OpenAI-compatible service with the user's own key, and grades answers by their goal rather than against one fixed solution.
Native, lean and tested
Both Windows apps were rewritten in Rust for 2.0. Rogeha Capture went from 52 MB to 527 KB and idles at under 2 MB of memory; Rogeha Deutsch C1 from 59 MB to 955 KB, reading the data 1.0 left behind. Automated tests guard each one: 55 and 73 of them.
Offline first, shared
go poschte keeps its list on the phone and syncs the household through the cloud when there is signal, so it works in a basement shop. Rogeha Capture needs no network at all.
Speech, both ways
Rogeha Deutsch C1 reads exercises aloud in natural Azure voices and takes answers by voice, streamed live so the words appear while you speak, with Windows voice typing as the fallback when there is no Azure key.
Connected devices
Hue Daylight drives Philips Hue lights from MeteoSwiss's sunlight forecast. It talks to the bridge on the home network over HTTPS pinned to the bridge's own certificate, and does its work in the background within Android's limits.
The last stretch, from working build to a product in people's hands, is where projects usually stall, and it is the part that is hard to judge from the outside. It is also where the disciplines of regulated work pay off: clear requirements, risks named early, verification before release. Here it is all in one place, on apps you can open and try.