Timing with multiple devices

This article explains the benefits and trade-offs of timing an event with multiple devices

This article discusses the use of multiple devices in the timing of a race, and answers the following questions:

  • Can I use multiple devices to time multiple checkpoints in my race?
  • Should I use multiple devices?
  • How many licenses will I need?
  • Can I time the race with a second device, as a backup
  • Can I share the work of timing at the finish line, between two devices?


Can I use multiple devices to time multiple checkpoints in my race?

Yes! — as a mobile solution, this functionality is a big advantage to RaceSplitter.

We ourselves often time mountain trail running races, and will time runners both on a mountain peak, and the finish line. After the race, we’ll publish results from both checkpoints back to RaceSplitter.com — where they are combined into a single results set, containing two splits, which we’ll rename to, “Pike’s Peak” and “Finish Line”. Participants love to be able to see the evolution of their performance over the course of the event, “Look, I was 5th on top of the mountain, and ended up finishing 3rd!”

Here are some things to note:

  • Be sure to load the same race onto all devices, so that the start list data is consistent.
  • Only one device needs to start the race at the correct time; all other devices can start their timers afterwards. When RaceSplitter.com receives multiple results data, it will use the earliest received start time as the official race start, and will re-calculate all other times referenced to that.
  • Each device should be timing a different checkpoint, as RaceSplitter.com assumes that each results set it receives is for a different physical checkpoint.
  • As a consequence, it is not possible for multiple devices to time the same checkpoint.
  • On the other hand, it is possible for a single device to record multiple checkpoints, if those checkpoints are the same physical location (for example, a multi-lap race where the racers pass by the same checkpoint multiple times.)
  • Each device should be logged into the same RaceSplitter.com account, so that all of the published results are properly combined.

If you decide to use a single device to time multipe checkpoints you need to be aware of the following: Say you missed timing racer 167 the first time they passed you, but you did time them the second. RaceSplitter will insert that time entry into “Split 1”, instead of “Split 2”. You will need to manually correct such entries, by tapping on them (either during or after the race) and changing the lap number from 1 to 2.


Should I time my event with one device or multiple devices?

If your event has only one split (e.g. the finish line) then timing with a single device is fine. If your event will include multiple splits, then it’s recommended to use multiple devices.

Consider a triathlon, which could potentially have five “splits” to time:

  1. Enter transition from swim
  2. Exit transition on bike
  3. Enter transition from bike
  4. Exit transition on run
  5. Cross finish line from run

Technically, you could time such an event using RaceSplitter with a single device since RaceSplitter has an “auto-lap” feature. Here’s how that works — Say you time racer 123 on Split 1 (entering from the swim), when you then time them the second time (leaving the transition on the bike) RaceSplitter will automatically create the second split — and eventually the 3rd, 4th and 5th splits as well.
So why is it a bad idea to try to time a triathlon in this way? For two reasons:

  1. You will sometimes miss timing a person in a given split. For example, you might time racer 185 on Split 2 (exiting the transition on the bike) but have missed timing them in Split 1. RaceSplitter will place that Split 2 time, however, in Split 1 since at that moment it has no time for racer 185 in Split 1 (and can’t possibly know that you missed them in Split 1). When this happens, you have to manually go back and edit the split number on these entries.
  2. Worse, is that sometimes you’ll accidentally time a given bib number twice in the same split. Say you time racer 123 on Split 1, and a few minutes later racer 132 comes along. But instead of typing 132, you accidentally type 123 — resulting in an erroneous second timing of that racer. RaceSplitter will happily create an additional (erroneous) split on the race, to support that subsequent (erroneous) timing of racer 123. RaceSplitter supports manual cleanup of these kinds of mistakes as well, but it can be confusing and messy to do that.

To avoid these problems, the best way to time such an event would be to dedicate a device to timing each split, and then disable the auto-split feature on the race, so that each device is limited to timing a single split. In this case, duplicate entries created on any device (e.g. a duplicate of 123) would generate a timing entry like 10123 — i.e. a number that should not exist in the start list, and contains the information needed to understand what bib you tried to time (“123” in this case). This makes it easier to identify and correct those duplicate entries later.

Using RaceSplitter on multiple devices doesn’t necessarily require multiple purchases of the app, since the app can be installed on any device that’s logged into the same iTunes (Apple) account used for the original purchase.


How many licenses will I need?

With a single purchase of RaceSplitter, you can install the app on any devices which are connected to the same iTunes account (which is different from your RaceSplitter.com account.) We are not aware if Apple place any restrictions on the number of devices. In our own case, we have RaceSplitter installed on at least five devices, with a single iTunes purchase.


Can I time the race with a second device, as a backup?

Yes, just download the same race to both devices, so that the start list data is consistent. Note that only one of the devices should publish its results back to RaceSplitter.com, as the website will treat each set of received data, as a separate checkpoint on the course.


Can I share the work of timing at the finish line, between two devices?

RaceSplitter doesn’t natively support the notion of sharing the timing of any given checkpoint (like the finish line) for a single race, with multiple devices. If you do decide to do this, please note the following:

  1. You can not view the race standings within RaceSplitter, as one device will not have access to the data recorded on the other.
  2. You can not publish results to RaceSplitter.com, as the website will treat each set of received data as a separate checkpoint on the course. It can not merge data from multiple devices at a single checkpoint.
  3. Your only alternative for working with your data after the race will be to export both results sets as CSV, and then combine them manually in a program like Excel.

Note that this refers to timing of a single race at the finish line, with multiple devices. Of course, if you have multiple races happening in parallel (say a 5k, 10k and half-marathon), and you plan to have three devices at the finish line, each timing a different race, then that’s perfectly fine.

Beyond the basics

After you've read the Getting Started Tutorial, dive deeper into more advanced topics.

Planning your event

As you plan the timing of your first event, here's what you'll want to think about.

Start types

RaceSplitter supports four race start types — mass, interval, wave and variable.


While the RaceSplitter app supports a single user-defined field, complex categorization is supported at the RaceSplitter website.



This article explains how to publish, export and edit your results, both in the app and online.

Multiple Devices

Easily time intermediate points on the course, with RaceSplitter's multi-device support.

Auto-split Mode

Auto-split mode is useful for timing multi-lap races, but should be disabled for most others.

Bibless timing

This article explains how to create timing entries in rapid-fire mode without entering bib numbers.

The Timing Bar

The RaceSplitter "timing bar" allows you to assign the same time to multiple racers — useful when timing groups of people arriving together.

Racer Compensation

RaceSplitter supports the application of compensation factors in adaptive and handicap sports.

Automatic start time adjustment

Under certain circumstances, RaceSplitter will automatically adjust the race start time. This is both a benefit, and a risk.

We’re here to help!

If you’ve been unable to find what you’re looking for, don’t hesitate to contact us, and we’ll get back to you shortly.

Support Email: [email protected]