Web · Racing
Gotland Ring
Drive Gotland Ring in your browser with keyboard or touch controls.
Play in browserRacing, science, and everyday tools — made in Sweden.
Web · Racing
Drive Gotland Ring in your browser with keyboard or touch controls.
Play in browser
iPhone & iPad · Utilities
Check your Bluetooth headset before a call. Hear your microphone through your headset and watch live input and output waveforms, with no recordings, uploads, or account.

iPhone · Education
Explore viscous flow around an airfoil. Adjust its shape, angle, and Reynolds number, then watch lift, drag, and vortices evolve alongside the classical potential-flow solution.

iPhone · Food & Drink
Scan packaged food and see its protein-to-energy ratio at a glance. Save products and recipes locally, with no account, ads, analytics, or tracking.

Mac · Education
A 2D turbulence simulator, CPU benchmark, and desktop background tool that turns numerical fluid dynamics into a live visual surface.

iPhone · Education
Direct numerical simulation of two-dimensional incompressible turbulence, updated for modern iPhones with richer resolution and higher Reynolds numbers.

iPhone · Education
Explore double through octuple pendulums, now rendered edge-to-edge in Metal. Tilt your phone and watch order tip beautifully into chaos.

iPhone & iPad · Education
Shape an airfoil with your fingertips and see the streamlines and pressure distribution respond — an interactive introduction to aerodynamic lift.

iPhone · Education
A simple physical system with wonderfully complex behavior. Tilt your device to influence a Runge–Kutta simulation of coupled motion.

iPhone · Education
Three linked pendulums turn deterministic equations into surprising motion. A pocket-sized demonstration of sensitivity and chaos.

iPhone · Medical
A visual timer that makes remaining time easy to understand. Designed for routines, focus, homework, and anyone who benefits from seeing time.

Mac · Education
Real-time 3D turbulence on the Mac, pairing a spectral Navier–Stokes solver with a GPU volume ray marcher and live scientific diagnostics.

iPhone · Education
Hold a living three-dimensional turbulence simulation in your hand. Orbit the flow, switch scientific fields, and inspect the energy spectrum in real time.
No apps in this view.
Built by Torbjörn Sjögren
Mannetroll Solutions AB is a one-person software studio in Sweden. The work sits where computational physics, practical tools, and the pleasure of understanding something meet.
No growth loops. No sprawling platforms. Just focused apps for the web and Apple devices that do one interesting thing well.