Redline: Sprint Timer
Sprint Intervals for Runners
About
This app simplifies sprint interval training for runners. It provides customizable countdowns, voice cues, and haptic feedback for each sprint and rest period. Sessions sync with Apple Health and can be controlled via Apple Watch and the Lock Screen.
What's New in Redline
1.1.0
September 24, 2026
1.1 is sleeker and more physical. New: - Coach voices: Straight, Drill Sergeant, or Deadpan. Pick one in Settings and tap to hear it first. - A real launch sequence: the last 3 seconds before every sprint slam in, oversized, building to GO. - The lane fills live as you run and lights up the instant each sprint ends. - A sharper haptic on every sprint finish. Also improved: a session now survives if iOS closes the app mid-workout, and your coach voice syncs between iPhone and Watch.
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FAQ
How do I set up a sprint workout in Redline?
Setting up a workout is designed to be quick. You can select the number of sprints, the duration of each sprint, and the length of rest periods. The default setting is six 30-second sprints with three minutes of rest, allowing you to start most sessions with a single tap.
Does Redline have ads?
No, Redline is completely ad-free. The app is designed to provide a distraction-free experience for your workouts, with no advertisements to interrupt your training sessions.
Can I use Redline without my iPhone?
Yes, Redline functions as a full workout app on Apple Watch. You can start sessions directly from your wrist, and transitions will be communicated via haptic taps and voice cues if you are using AirPods.
How does Redline sync with Apple Health?
Every completed session in Redline is automatically saved to Apple Health as a high-intensity interval workout. Each sprint within the session is recorded as a distinct segment, and if run from the Watch, it also includes heart rate and energy expenditure data.
What is the age rating for Redline?
Redline has an age rating of 4+. This indicates it is suitable for users of all ages, with no content restrictions.
How often is Redline updated?
The latest version of Redline is 1.0.2, which was last updated on September 17, 2026. While specific update frequency isn't detailed, this indicates recent maintenance and potential for future improvements.
What makes Redline different from other interval timers?
Redline focuses on simplicity and a distraction-free experience. It avoids accounts, logins, and subscriptions, offering only the core functionality of a sprint timer with clear voice cues and seamless integration with Apple devices.
Is Redline available on other devices besides iPhone and Apple Watch?
Currently, Redline is designed for iPhone and Apple Watch. The app leverages the unique features of these devices, such as haptic feedback on the Watch and Live Activities on the iPhone's Lock Screen.
