Race Start Simulation

The Swim Start app is a training aid for swimming race start practice.

It is compatible with the iPhone, iPad and iPod touch

Start swim groups at fixed intervals with “Take Your Marks” and “GO” sounds.
Use an external speaker attached to an iPhone or iPad for improved sound volume.


Select built-in or custom “Take Your Marks” and ‘Go’ signal sounds.

Sample “Take Your Marks” sound.

Sample “GO” signal.

Continuous or Limited
  • Enable continuous mode or limit to a specified number of race repetitions.
  • Select Repeat Interval. Default is every 10 seconds.
Starters Pause
  • The pause between the “On Your Marks” and “Go” sounds.
  • Can be a Fixed or Random pause time from one repetition to the next.
  • When Fixed Pause is enabled:
    • Set the fixed pause time between “On Your Marks” and “Go” sound.
    • The pause range is 0.5 to 2 seconds.
Sync to External Clock
  • Synchronise the SwimStart app to an external swim clock on the pool deck.
  • Start at either Red or Black top.
Remote Control and Replication

The Remote Control and Replication feature allows several remote iOS devices running SwimStart to connect to a Primary iOS device (running swim start).

  • Multiple remote iOS devices will replicate the Primary.
  • Remote units can start/stop Primary.
  • Primary will start/stop all connected remote units.
  • Range can be up to 100m depending on obstacles.
  • Only available on newer iOS devices with Bluetooth Low Energy (BLE) hardware.
Swim Start App Info

Version: 1.3.0
Updated: May 29, 2018
Requires iOS 9.3 or later.
Device Family:  iPhone, iPad and iPod touch.
Category: Sports
Author: David Mayes
© David Mayes 2018
Rated 4+

Screen Shots




Settings Menu Guide

The following is a brief description of each of the items in the settings menu.

Repetition Configuration

This section allows the user to configure timing parameters related to the “On your marks” and “GO” signals.

Starters Pause

This is the pause time between the “On your marks” sound and the “GO” sound.

  • The default is a fixed pause time of 2.0 seconds.
  • The step resolution is 100 milli seconds.
  • Disable fixed mode and the pause time will be random by up to 2.4 seconds.
Repeat Interval

This is the time in seconds between “GO” signals.

  • The default is 10 seconds.
  • The step resolution is 10 seconds.
Enable Continuous mode

When enabled, the “On your marks” and “GO” signals will be repeated forever at the repeat interval, or until the stop button is pressed.

When disabled the user can set the race repetitions to limit the number of repeats.

Race Repetitions

This is simply the number of times that the “On your marks” and “GO” signals will be played.


This section provides selection of the “On your marks” and “GO” sounds.
There are several built in sounds available or custom sounds can be selected from your music library.

On Your Marks Sound
  • This is the sound played just prior to the start signal.
  • The default is a recording of a person saying “On your marks”
  • Select a custom sound from your music library.
  • Custom “On your marks” sounds must be less than 2 seconds.
Go Sound
  • Is the sound played when the count down ticker reaches zero (“GO”).
  • The default is a short burst siren.
  • Select a custom sound from your music library.
Custom Sounds:
  • Can be copied into the music library on your Apple device via iTunes.
  • File format must be either mp3 or m4a.
  • Are limited to a maximum of 2 seconds.

Pace Clock

Synchronise the SwimStart app to an external pace clock.

If the swimmers can’t see the Swim Start count down ticker, or prefer using the big pace clock on the wall, then you are able to synchronise the Swim Start pace clock to the external clock.

Remote Control/Replicate

When Swim Start is configured for remote mode, it can Start and Stop another device running Swim Start in Primary mode.

Swim Start running in Remote mode will synchronise the pace clock and count down ticker with the Primary.

Enable Remote Control
  • Enables remote control and replicate mode.
  • Must have bluetooth enabled.
  • The device must support Bluetooth Low Energy.
  • Select either Primary or Remote modes.
  • There must be one Primary SwimStart enabled.
  • When Remote is selected there must be another Primary device already configured.
Connect to:
  • When Remote mode is selected you must choose a Primary device to connect to.
  • Multiple remotes may connect to one Primary device.


Swim Start is a simple training aid for race start practice.

It is an Apple iOS app compatible with iPhone, iPad and iPod touch.

Start swim groups at fixed intervals with configurable “Take Your Marks” and “GO” sounds.

Swim Start simplifies the coaches job by providing an automated starter at the swim blocks, allowing coaches to position themselves at other locations around the pool to monitor and record swimmers performance.

The Swim Start app can be controlled remotely with your iPhone.

About the author : David Mayes

I swim to keep fit with a Masters swim squad.

My coach, Alan Godfrey, asked if anyone knew of an app that could emit a start tone every 10 seconds so he didn’t have to run from one end of the pool to the other when timing 50m sprints.  The SwimStart app was born.

Apple iOS programming is a completely different field of programming for me and has been a very interesting challenge.

If you have any questions please leave a message via the contact form below  and I will endeavour to get back to you with some answers.



If you have an issue, need clarification or a request for a new feature, please get in touch by submitting a message here.