Comparison

σT vs iTurbo3D

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

σT

Features
Read full description

σT is a precision tool for physics students and researchers who need to propagate measurement uncertainties through calculations. Enter your experimental data, and σT handles the error math automatically. **FIVE ERROR MODES** Configure uncertainties in your data to match your orignal measurement method: • Constant — for physical constants and exact values • Absolute — fixed ±error (ruler measurements, digital readouts) • Relative — percentage-based uncertainty • Combined — both absolute and relative components (many typical multimeters) • Per-Value — individual error for each measurement **AUTOMATIC PROPAGATION** Create derived values and watch uncertainties flow through the calculation chain. σT uses Gaussian error-propagation and pre-calculated derivative-based methods to compute propagated errors correctly when combining independently measured variables. Available operations: • Basic: add, subtract, multiply, divide, reciprocal • Functions: exp, ln, sin, cos, normalize • Statistical & Sample Statistics: mean with standard error, average step width • Advanced: weighted sums, weighted products, polynomials • Physics: Lorentz factor (relativistic gamma), Logit sigmoid (Fermi-Dirac statistics) **INTERACTIVE CHARTS** Visualize your data with proper error bars. Pinch to zoom, drag to pan, double-tap to auto-fit. Add mathematical function overlays to compare your measurements against theoretical predictions, identify eligible parameter ranges matching your measurements. **EXPORT YOUR WORK** • CSV and TSV export for spreadsheets and analysis tools • High-resolution PNG charts for lab reports • Complete project files for sharing with classmates or colleagues • Copy data to clipboard with a swipe and continue in Sheets or Excel with errors in place **DESIGNED FOR LAB WORK** σT adapts to your device: • iPhone: Full-featured portable lab companion • iPad: Side-by-side layout for efficient data entry • Mac: Native desktop experience via Catalyst **YOUR DATA, YOUR DEVICE** All measurements are stored locally. No account required, no cloud sync, no tracking. σT works completely offline.

About

iTurbo3D

Features
Read full description

iTurbo 3D brings interactive three-dimensional turbulence simulation to iPhone. A pseudo-spectral incompressible Navier-Stokes solver evolves the velocity field while a Metal volume ray marcher displays the flow as it develops. Explore the volume using touch controls: drag to orbit, pinch to zoom, and double-tap to restore the camera. Switch between vorticity, Q-criterion, kinetic energy, and helicity, with a selection of scientific colormaps and light or dark backgrounds. Configure Taylor-Green or random turbulence, choose a 32 cubed, 64 cubed, or 128 cubed grid, set the Reynolds number, and adjust forcing. Higher grid resolutions reveal finer structures while using progressively more memory and processing power. Pause, resume, advance one step, or reset the simulation from the bottom toolbar. Live status values show the time step, iteration, simulation time, step rate, energy, and enstrophy. Expand the diagnostics to inspect energy history and the energy spectrum. Whether you are teaching fluid mechanics, studying turbulence, or simply enjoy computational physics, iTurbo 3D turns the equations of motion into something you can see and explore directly on iPhone.

Screenshots

σT4 screens
iTurbo3D4 screens

Verdict

The call

The clearest difference is iOS requirement: iTurbo3D at 18.0 against σT's 26.2. On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Scorecard1 real difference · 5 level
σT versus iTurbo3D: the parameters behind the verdict, then further details
ParameterσTiTurbo3D
PriceFreeFree
Update frequencyFortnightly—
AdsNoNo
In-app purchasesNoNo
DevicesiPhone, iPad — betteriPhone
Requires iOS26.218.0 — better
Further details — not scored
Size6 MB1 MB
Age rating4+4+
DeveloperYARON AMIR BENJAMIN DR. GOLDSTEINManneTroll Solutions

In-app purchases

None

σT

No in-app purchases

None

iTurbo3D

No in-app purchases

Questions

Is σT free?
σT is free to download, with no in-app purchases.
Is iTurbo3D free?
iTurbo3D is free to download, with no in-app purchases.
Do σT or iTurbo3D have ads?
Neither σT nor iTurbo3D shows ads.

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