Comparison

PIDTune vs NK

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

Head to head
About

PIDTune

This utility calculates PID tuning parameters using the IMC method for various process and controller types. It allows for direct input of process gain or variable changes, with adjustable tuning aggression via a slider.

Highlights
  • IMC method for PID tuning
  • Calculates Kc, Ti, Td
  • Supports FO, SO, and I process types
  • Handles Parallel and Series controller types
  • Adjustable tuning aggression slider
  • Input process gain or variable changes
Features
Read full description

PID Tuner uses the IMC (Internal Model Control) method to calculate PID tuning parameters. I’ve tried a lot of tuning methods over the years and have found this one to be the best. The app is written for the iPad to show all the information on one page. The program calculates: PID Parameters: Controller Gain (Kc) Integral Time (Ti) Derivative Time (Td) For process types First Order with Dead Time (FO) Second Order with Dead Time (SO) Integrating or Long Time Constant with Dead Time (I) For controller types Parallel (non-interacting) c(s) = Kc (1 + 1/(Ti s) + Td s) Series (interacting) c(s) = Kc (Ti s + 1)/(Ti s)(Td s + 1) For controller modes PID PI You can either enter the process gain (Kp) directly or enter the changes in the controlled virable (CV) and manipulated variable (MV). Tuning aggression is adjusted using the slider to set the closed loop time constant to the process time constant ratio (λ/Ƭ). The closed loop time constant (λ) is the time the controller is expected to reach set point (plus the dead time (ϴ)). Setting the closed loop time constant to process time constant ratio (λ/Ƭ) to 1.0 will make the MV change to its final value and allow the process to settle out to the setpoint. Setting (λ/Ƭ) greater than 1.0 will give a slower responce. Setting (λ/Ƭ) less than 1.0 will cause the MV to make a larger change and then reduce to its final value. Tight tuning would be to set the close loop time constant to the dead time. Use the Integrating Process type (Ƭ = ∞) for both integrating processes or processes with long time constants. These processes use the maximum slope as the process gain. Tuning aggression for these processes is determined by setting the closed loop time constant to the dead time ratio (λ/ϴ). Once again, setting the closed loop time constat to the dead time gives tight control. References: “Probably the test simple PID tuning rules in the World,” Sigurd Skogestad, Jounal of Process Control, July 3, 2001 “Consider the generalized IMC-PID method for PID controller tuning of time-delay processes,” Y. Lee, S. Park, M. Lee, Hydrocarbon Processing, January 2006

About

NK

Features
Currently charting
Read full description

**Function Application** - Easy install - Real-Time Tuning - Anti-Theft - 3 Mode - Calibration - Injector Tuning (-50 to 50) % - Ignition Tuning(-50 to 20) DEG - Idle Ramble - Compensate Tuning - Analyze - TPS Enrichment Tuning - Fuel start Tuning - Digital I/O - Data Log - BARO compensate

Screenshots

PIDTune3 screens
NK3 screens

Verdict

The call

The clearest difference is ads: PIDTune at none against NK's shown. PIDTune also leads on price ($4.99 vs $9.99). NK's advantage is chart position (#197 vs unranked) and iOS requirement (12.0 vs 15.0). On update cadence, 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

PIDTune costs $4.99 and NK $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

PIDTune ships an update every 4 months, NK every 3 months. The most recent releases landed on October 8, 2026 and October 14, 2026 respectively.

Scorecard4 real differences · 7 level
PIDTune versus NK: the parameters behind the verdict, then further details
ParameterPIDTuneNK
Price$4.99 — better$9.99
Rating5.0 (2 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings2 — better—
Update frequencyEvery 4 monthsEvery 3 months — better
AdsNo — betterYes
In-app purchasesNoNo
MonetizationPaid—
Best chart rank—#197 — better
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS15.012.0 — better
Further details — not scored
Size1 MB80 MB
Age rating4+4+
DeveloperRichard H StreetNK RACING PARTS COMPANY LIMITED

In-app purchases

None

PIDTune

No in-app purchases

None

NK

No in-app purchases

Questions

Is PIDTune free?
PIDTune costs $4.99, with no in-app purchases.
Is NK free?
NK costs $9.99, with no in-app purchases.
Do PIDTune or NK have ads?
NK shows ads; PIDTune does not.
Which is updated more often, PIDTune or NK?
PIDTune ships an update every 4 months, and NK every 3 months. Most recently, PIDTune was updated on October 8, 2026 and NK on October 14, 2026.

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