ChronoMaster vs GPS Rally Computer
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
ChronoMaster
This app is designed for classic car rally pilots and co-pilots to precisely navigate complex special stages. It offers 1/100s second accuracy for timing and distance, with a graphical interface to manage interlaced stages, average speed controls, and countdown timers.
- 1/100s second precision timing
- Graphical interface for complex stages
- Acoustic countdown timer
- Automatic average speed calculation
- Transfer stage data from roadbook
- Bilingual interface (English/German)
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A must have for the serious classic car rallye pilot & co-pilot with a passion to win. Classic car rallies are usually conducted as regularity rallies with so called "Special Stages" which require the pilot to drive a specific distance in a predefined time. Simple Special Stages comprise of just one sector (e.g. 100 meters in 10 seconds). However more serious rallies such as the Mille Miglia require you to master sets of complex, interlaced Special Stages or to maintain a predefined average speed across a stage. ChronoMaster lets you master even the most complicated special-stages of a classic car rallye with ease and 1/100s of a second precision. Don’t get distracted by confusing interlaced stages, secret average speed controls, light-barriers and tubes. ChronoMaster does what most expensive rallye-computers promise – at a fraction of the cost! And it is more intuitive to use on the iPad’s large & bright screen with a full graphical interface. - Transfer all data of a day’s special stages from the roadbook to the iPad before the rallye starts - Easy to use graphical interface to enter special stage data (time, distance, average speed) - Full graphical representation of special stage, including individual/interlaced sectors, light-barriers, tubes - Select the special stage from a list – and off you go! - Up to 15 sectors/special stage - Unlimited number of special stages - Acoustic countdown timer for last 10 seconds of special stage/sector (earphone recommended for driver) - Displays most important information during special stage: time to go, distance from start, distance to finish, average speed of stage/sector - Automatically calculates average speed based on stage-distance/time - No more stopwatch or average-speed tables required - Simple interface lets you concentrate on navigation and precision driving - Sector target time can be input with up to 1/10sec accuracy (e.g. 21.3 sec) - Maximum distance of a special stage is 99.999km - Zero-sync - start multiple sectors of a special stage at once - Start-buttons can be adjusted for left/righthand use (To use start-buttons most precisely during rallying on bumpy roads, place your thumb on the start button, hold it and release button upon start) - Bilingual user interface (English/German) Good luck and most of success with your next classic rallye! ==== Version History ==== v 1.3 NEW: Start-beep does now allow acoustic control of the start which will result in even higher precision during Special Stages. v 1.2 NEW: Up to 15 sectors/stage NEW: Larger digits in the countdown-timer for better usability NEW: English Version NEW: ChronoMaster's functionality is independent of units (kilometers/miles) - although it currently only displays metric units (km/m) just input Special Stage distances in miles as indicated in the roadbook (e.g. 3.7 miles), disregard the displayed "km" unit - and off you go! v 1.1 NEW: Sector target time can input now with 1/10sec accuracy (e.g. 21.3 sec) NEW: Maximum distance of a special stage now 99.999km NEW: Zero-sync - start multiple sectors at once
GPS Rally Computer
This app aids in navigating traditional time-speed-distance (TSD) automobile rallies by simplifying complex computations. It allows for odometer calibration, precise speed tracking, and real-time error correction to help drivers stay on pace.
- Odometer calibration
- Precise speed tracking
- Real-time error correction
- Adjustable clock and distance units
- Customizable speed changes
- Time and distance recording
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GPS Rally Computer is a Universal app designed to simplify computations necessary to navigate a traditional time-speed-distance (TSD) automobile rally. The design and implementation is based on specifications outlined by Clarence Westburg and Rich Bireta, commonly known as the Simple Rally Computer or its acronym SRC. The User's Manual is available on the app detail page linked at http://www.msyapps.com. A TSD rally is comprised of stages set along a route defined by written instructions. The first stage is the Odometer Check stage that allows you to calibrate your car’s odometer with that of the Rally Master’s odometer. In later stages you will follow a course at a particular average speed that will change from time to time at places that are generally unknown in advance. In order to drive the course at the prescribed speeds. Odometer measurement is obtained from Apple’s GPS receiver or third-party devices via Bluetooth. The GPS Rally Computer allows you to do all this and much, much more. For additional documentation, download the User’s Guide. Features of the GPS Rally Computer: - Clock time in either minutes and seconds to tenths of a second or decimal minutes to thousandths of a minute - The clock is a 24-hour clock to simplify computations - Distance measurements in either miles or kilometers to either two- or three-digit precision - One button click to reset default conditions for starting a rally - The internal computer clock can be adjusted to match the official rally clock - The distance between the GPS receiver and the position on the car where the rally measurements are taken (the front wheels, for example) can be added for improved distance precision - A "sprocket" button in the top menu bar allows access to the app settings from within the running application including settings for display of certain items - Calibrate the car's odometer to the official rally odometer on the odometer check stage via a popup - Change average speed (CAST) on a custom popup keypad - Preselect the next CAST to simplify the process of changing speed on each stage and setting CAST to zero for transit zones - As time passes and as the car's odometer is incremented, the actual speed over the course is compared with the expected speed. The difference in seconds or hundredths of a minute is displayed along with an indication to either “Early” or “Late” to stay on pace. - Time errors may be displayed in either of two modes selectable in the app Settings - Pause or Gain time or take a Time Allowance on any leg or within a transit zone - Handle off-course corrections to time and distance with a Reverse button - Record "splits" of time and error at any time with a Split button - Record "control" and reset time error and distance to zero and increment next starting time 5 minutes later (distance and time are modifiable) with a Control button. - Set next starting time for the Next CAST and have the time tick down on the master clock and autostart CAST, or override with a manual button click - Optionally, use a Dual GPS receiver via Bluetooth to supplement or substitute for the Apple internal GPS - Connects to TSD Remote app that serves as a driver's heads-up display connected via local network. Note: Use of the GPS Rally Computer during any particular rally will be subject to the rules and instructions governing the rally and may also define your category or class among race participants. Some rallies may, in fact, prohibit use of this app. This app has been tested with Bluetooth connectivity to a Dual XGPS150A Universal GPS Receiver. Disclaimer: Continued use of GPS running in the background can dramatically decrease battery life.
Screenshots
Verdict
The clearest difference is price: GPS Rally Computer at $24.99 against ChronoMaster's $64.99. GPS Rally Computer also leads on update cadence (monthly vs every 9 months) and device support (3 vs 1). ChronoMaster's advantage is iOS requirement (9 vs 12.4). On ads, in-app purchases and monetization model 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
ChronoMaster costs $64.99 and GPS Rally Computer $24.99 up front. Neither carries in-app purchases, so what you see is what you pay.
ChronoMaster ships an update every 9 months, GPS Rally Computer monthly. The most recent releases landed on June 5, 2026 and September 19, 2026 respectively.
| Parameter | ChronoMaster | GPS Rally Computer |
|---|---|---|
| Price | $64.99 | $24.99 — better |
| Rating | — | 3.8 (5 ratings) — better |
| Positive reviews | 0.0% of reviews | — |
| Number of ratings | — | 5 — better |
| Update frequency | Every 9 months | Monthly — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Devices | iPad | iPhone, iPad, iPod — better |
| Requires iOS | 9 — better | 12.4 |
| Further details — not scored | ||
| Size | 4 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | BrandsOnSpeed GmbH | MSYapps |
Customer experience
ChronoMaster
GPS Rally Computer
In-app purchases
ChronoMaster
No in-app purchases
GPS Rally Computer
No in-app purchases
Questions
Is ChronoMaster free?
Is GPS Rally Computer free?
Do ChronoMaster or GPS Rally Computer have ads?
Which is updated more often, ChronoMaster or GPS Rally Computer?
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