GPS Rally Computer
rallies that allow GPS odos
$24.99
5.3.1for iPhone, iPad and more
Age Rating
GPS Rally Computer Screenshots
About GPS Rally Computer
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.
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.
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What's New in the Latest Version 5.3.1
Last updated on Feb 7, 2024
Old Versions
- Updated info.plist file to improve peer-to-peer connectivity to the TSD Remote heads-up display app.
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Version History
5.3.1
Feb 7, 2024
- Updated info.plist file to improve peer-to-peer connectivity to the TSD Remote heads-up display app.
5.3
Sep 9, 2023
- Fixed GUI display issue with iPad version.
5.2
Mar 16, 2020
- Recalibrated filter rules to minimize distance creep while stopped or nearly stopped.
- Fixed bug in odometer correction factor routine and improved its functionality.
- Added 0 and 00 as allowable digits when initiating or editing odometer correction factor.
- Fixed bug that prevented Pause or Gain during a Transit Zone after adjusting the odometer with the "bump" feature.
- Improved the computation of distance estimates between GPS signals.
- Minor GUI changes.
- Fixed bug in odometer correction factor routine and improved its functionality.
- Added 0 and 00 as allowable digits when initiating or editing odometer correction factor.
- Fixed bug that prevented Pause or Gain during a Transit Zone after adjusting the odometer with the "bump" feature.
- Improved the computation of distance estimates between GPS signals.
- Minor GUI changes.
5.1
Feb 15, 2020
- The major code improvements and additions are designed to adjust the GPS coordinates of a moving vehicle owing to the time between reception of new GPS signals and to the time lag between the time the signal was generated from satellites and the time when processing actually occurs in the app.
- Users may now adjust the location coordinate by the distance between the GPS receiver in the car (either the iPhone or iPad or some third-party GPS receiver) and the position on the car where a rally may measure time or location at timed controls (sometimes this is the front of the car or the center of the front wheels). This optional adjustment is available in the Reset popup.
- All three of these potential errors in coordinate measurement are discussed at length in a 6-part thread in the Facebook "Road Rally Tech Talk" forum.
- If clock and GPS device distance adjustments are non-zero, an indication of the adjustments selected will be shown in the upper center of the display beneath the app title.
- If available to the app, compass coordinates are available to verify location when the car is stopped. The compass coordinates and bearing are available from a "compass" button on the "Map" popup.
- The "gps" information display button and contents have been relocated to the "Map" popup. Also, there are two new pieces of information on the display: Time Lag, the difference between the time the GPS signal was generated and the time when the new GPS location is actually processed in the app; and Signal Interval, the time between each receipt of new GPS information from the GPS receiver, either Apple's internal receiver/processor or a third-party GPS receiver.
- Various improvements to the processing of information from the Dual 150 and 160 model GPS receivers.
- Changes to processing of Apple internal GPS signals to account for spurious readings when horizontal accuracy is poor or when the car is stopped or moving very slowly.
- Odometer synchronization has been removed from the "Odo" popup. Rather, you may use the "Adjust Odo" option to set, reset, or adjust the odometer as needed.
- Various, relatively minor GUI changes.
- Coding for displays has been reduced and simplified where possible.
- Users may now adjust the location coordinate by the distance between the GPS receiver in the car (either the iPhone or iPad or some third-party GPS receiver) and the position on the car where a rally may measure time or location at timed controls (sometimes this is the front of the car or the center of the front wheels). This optional adjustment is available in the Reset popup.
- All three of these potential errors in coordinate measurement are discussed at length in a 6-part thread in the Facebook "Road Rally Tech Talk" forum.
- If clock and GPS device distance adjustments are non-zero, an indication of the adjustments selected will be shown in the upper center of the display beneath the app title.
- If available to the app, compass coordinates are available to verify location when the car is stopped. The compass coordinates and bearing are available from a "compass" button on the "Map" popup.
- The "gps" information display button and contents have been relocated to the "Map" popup. Also, there are two new pieces of information on the display: Time Lag, the difference between the time the GPS signal was generated and the time when the new GPS location is actually processed in the app; and Signal Interval, the time between each receipt of new GPS information from the GPS receiver, either Apple's internal receiver/processor or a third-party GPS receiver.
- Various improvements to the processing of information from the Dual 150 and 160 model GPS receivers.
- Changes to processing of Apple internal GPS signals to account for spurious readings when horizontal accuracy is poor or when the car is stopped or moving very slowly.
- Odometer synchronization has been removed from the "Odo" popup. Rather, you may use the "Adjust Odo" option to set, reset, or adjust the odometer as needed.
- Various, relatively minor GUI changes.
- Coding for displays has been reduced and simplified where possible.
5.0.67
Jul 22, 2019
- For rallies where distance is measured in kilometers, CAST speed inputs can now be greater than 99.99.
- Various GUI modifications and code changes to accommodate this option.
- Distance measurement Setting of either miles or kilometers must be made before starting the rally or after a full reset to default conditions. In other words, the distance cannot be changed while the app is running during the rally.
- Various GUI modifications and code changes to accommodate this option.
- Distance measurement Setting of either miles or kilometers must be made before starting the rally or after a full reset to default conditions. In other words, the distance cannot be changed while the app is running during the rally.
5.0.66
Dec 27, 2018
- Made time error value symbol (+ or -) the same on the Gauge view as in the Log.
5.0.65
Oct 8, 2018
- Fixed bug in time error computation while in Transit Zone.
5.0.64
Sep 28, 2018
- Changed the GUI of the "Number Only" Error Style to include up and down arrows.
5.0.63
Sep 14, 2018
- Some rallies do not have Pauses, Gains, or Time Allowances so this version introduces the option to Hide Display of these time options. If at any time during the rally these options are required, then simply select either Keypad Popup or Preset Times.
5.0.62
Jul 16, 2018
- GUI improvements on iPad version that involve the graphical display of time errors plus or minus.
5.0.61
Jul 11, 2018
- Squashed an annoying bug that at certain Cents starting times produced a time that was off by a few thousandths of a minute.
5.0.6
Jun 29, 2018
- At the start, after the odometer check leg, the 1st CAST happens at a particular point or outmarker, typically at zero distance, and at a particular time. Similarly, after a timed checkpoint or control, the start of the next stage will occur at a particular CAST and time. So, to make certain that teams input the correct CAST and Start Time, the CAST input popup will insert "req'd" in the CAST and Start Time fields. To continue, each field must have a valid input.
- Timed CAST at 1st CAST and at Control must be between T.O.D. -30 minutes and T.O.D. +30 minutes, or 0 minutes for Manual CAST by Unlocking & Clicking. Next CAST must be 0 minutes for Manual CAST or T.O.D. + minutes/seconds only for Timed CAST.
- On the CAST xx.xx button the color is now green to indicate the locked position for the 1st CAST and Curr CAST. When to button is unlocked, the color will change to red and importantly the CAST xx.xx will be the Next CAST. This change was done to allow the driver and navigator to see the Current CAST at a glance and the Next CAST only when unlocked.
- To further emphasize the locked and unlocked positions of the CAST xx.xx button, the words "locked" and "unlocked" have been added beside the icon button.
- The Settings have been relocated to the center of the display. Also, the settings themselves are now saved to a file so that settings you have made will persist even after closing and restarting the app.
- The color of the Control button has been changed to red to reinforce the notion that a Control or Checkpoint is an end of a leg.
- Fixed bug when Start Time is precisely 60:00 or 60.00 minutes.
- GUI tweaks and some added text notes on displays.
- Timed CAST at 1st CAST and at Control must be between T.O.D. -30 minutes and T.O.D. +30 minutes, or 0 minutes for Manual CAST by Unlocking & Clicking. Next CAST must be 0 minutes for Manual CAST or T.O.D. + minutes/seconds only for Timed CAST.
- On the CAST xx.xx button the color is now green to indicate the locked position for the 1st CAST and Curr CAST. When to button is unlocked, the color will change to red and importantly the CAST xx.xx will be the Next CAST. This change was done to allow the driver and navigator to see the Current CAST at a glance and the Next CAST only when unlocked.
- To further emphasize the locked and unlocked positions of the CAST xx.xx button, the words "locked" and "unlocked" have been added beside the icon button.
- The Settings have been relocated to the center of the display. Also, the settings themselves are now saved to a file so that settings you have made will persist even after closing and restarting the app.
- The color of the Control button has been changed to red to reinforce the notion that a Control or Checkpoint is an end of a leg.
- Fixed bug when Start Time is precisely 60:00 or 60.00 minutes.
- GUI tweaks and some added text notes on displays.
5.0.5
May 29, 2018
- Fixed bug in the computed ideal time clock during a transit zone. The clock should stop in the transit zone and only pause or gain increments should be added or subtracted if applied within the transit zone.
5.0.4
May 22, 2018
- Fixed bug that affected early start at outmarker when the time display was set to three digits.
5.0.3
May 18, 2018
- Added an option for Pause or Gain at user-defined preset seconds or cents. This will allow rapid Pauses or Gains that are quite common instructions in rallies. The option is available in the redesigned Settings, which is now a popup that can be selected within the app while running.
- The new Settings popup has two options for Measurement Settings (time and distance) and six options for Display Settings to change precision or to display options for time error and pause/gain with presets or pause/gain/time allowance with keypad entry. The Measurement Settings may only be set at before starting the rally while the Display Settings can be chosen at any time.
- Several bug fixes and GUI tweaks.
- The new Settings popup has two options for Measurement Settings (time and distance) and six options for Display Settings to change precision or to display options for time error and pause/gain with presets or pause/gain/time allowance with keypad entry. The Measurement Settings may only be set at before starting the rally while the Display Settings can be chosen at any time.
- Several bug fixes and GUI tweaks.
5.0.2
May 15, 2018
- Fixed bug affecting timing error if you make an early departure from an outmarker.
- Fixed bug affecting timing error if you include a pause, gain, or time allowance within a transit zone.
- Added an option to provide numeric entries in the CAST popup by means of buttons. So, now there are two options: keypad or buttons.
- Various GUI tweaks.
- Fixed bug affecting timing error if you include a pause, gain, or time allowance within a transit zone.
- Added an option to provide numeric entries in the CAST popup by means of buttons. So, now there are two options: keypad or buttons.
- Various GUI tweaks.
5.0.1
May 7, 2018
- Bug fix. If you touch the "Start at Outmarker CAST xx.xx" button, the "Computed Time" should be the time at which you are scheduled to depart the Outmarker. In other words, if you leave the Outmarker early, the time error will reflect the early start.
5.0
Apr 24, 2018
- Major redesign of the app that includes numerous code changes for improved logical flow, for fixing bugs, and for adding features or functionality.
- GUI tweaks and some added notes or label changes to convey more information to the user.
- Added "elapsed time" for each stage to the Log table.
- Added padlock icons to "lock" and "unlock" the "CAST xx.xx" button to prevent inadvertent or unintentional actions that might introduce errors in processing.
- Created separate "Split" and "Control" buttons rather than a combined button in earlier versions. Now, touching the "Split" button will immediately record time, speed, distance, etc. in the Log table. Touching the "Control" button will require a second button click to affirm or cancel the action. This should simplify the process and better distinguish Control actions from ordinary Splits done primarily for informational purposes.
- Pause, Gain, or Time Allowance can be added within a Transit Zone.
- Changed the "clear" button title to "BTZ" for Begin Transit Zone where the CAST should be zero in the view where these edits can be made.
- Distance in the Log table is now displayed to three decimal places.
- Distance in the Log table is now displayed to three decimal places.
- GUI tweaks and some added notes or label changes to convey more information to the user.
- Added "elapsed time" for each stage to the Log table.
- Added padlock icons to "lock" and "unlock" the "CAST xx.xx" button to prevent inadvertent or unintentional actions that might introduce errors in processing.
- Created separate "Split" and "Control" buttons rather than a combined button in earlier versions. Now, touching the "Split" button will immediately record time, speed, distance, etc. in the Log table. Touching the "Control" button will require a second button click to affirm or cancel the action. This should simplify the process and better distinguish Control actions from ordinary Splits done primarily for informational purposes.
- Pause, Gain, or Time Allowance can be added within a Transit Zone.
- Changed the "clear" button title to "BTZ" for Begin Transit Zone where the CAST should be zero in the view where these edits can be made.
- Distance in the Log table is now displayed to three decimal places.
- Distance in the Log table is now displayed to three decimal places.
4.4
Feb 9, 2018
- Added the option to increment odometer adjustments by 1.000, 0.100, 0.010, and 0.001 miles or kilometers. A popup list showing these options will be appear when you touch the "Pause to Adj" button. When you touch the "Resume Odo" button, the list will disappear.
4.3
Jan 12, 2018
-Added optional display of time errors with an animated dial graphic with colors to show pace ahead or behind ideal. The dial will display errors in whole numbers when greater than or equal to +/– 1 second and decimal numbers when nearer to zero. The options may be chosen in the app Settings.
4.2
Dec 17, 2017
- Added support for Rally Computer Remote app that serves as a driver's heads-up display connected via Bluetooth.
4.1.3
Dec 7, 2017
- Modified alert button font styles for better clarity
4.1.2
Nov 27, 2017
- Fixed bug related to setting new odometer distance for Next CAST. If there is a user input new odometer distance, the odometer distance will reset to this distance when the CAST xx.xx button is touched or when the CAST xx.xx is executed when the countdown time reaches zero time. Additionally, any distance difference between the new reset odometer distance and the displayed odometer distance will increment the time error based on the difference at the prior CAST.
- After an odometer check, the starting distance for the first stage will be reset to zero or another distance that the user may chose. If the distance is not equal to zero, then the time error will register error to that distance when the CAST xx.xx is touched.
- After an odometer check, the starting distance for the first stage will be reset to zero or another distance that the user may chose. If the distance is not equal to zero, then the time error will register error to that distance when the CAST xx.xx is touched.
4.1.1
Nov 18, 2017
- Added code to ensure that background location tracking will take place for at least 3 minutes permitted by Apple.
- GUI modifications for improved readability.
- GUI modifications for improved readability.
4.1
Oct 27, 2017
- Changed minimum required iOS version to 10.3 to resolve some issues and to accommodate new technology.
- Reduced from 10 meters to 1.5 meters (33 feet to 5 feet) the minimum distance computed from a pair of GPS coordinates suitable for incrementing distance. This improves displayed distance measurement to 0.001 mile accuracy, which is especially important at speeds less than 15 mph.
- Various changes to accommodate iOS 11.
- Reduced from 10 meters to 1.5 meters (33 feet to 5 feet) the minimum distance computed from a pair of GPS coordinates suitable for incrementing distance. This improves displayed distance measurement to 0.001 mile accuracy, which is especially important at speeds less than 15 mph.
- Various changes to accommodate iOS 11.
GPS Rally Computer FAQ
Click here to learn how to download GPS Rally Computer in restricted country or region.
Check the following list to see the minimum requirements of GPS Rally Computer.
iPhone
Requires iOS 12.4 or later.
iPad
Requires iPadOS 12.4 or later.
iPod touch
Requires iOS 12.4 or later.
GPS Rally Computer supports English
