We took a music player, combined it with a state-of-the-art beat analyzer, dynamic gait detector, and high fidelity audio time stretcher, then hid all the advanced technology under the hood. The result is magical: a simple, easy-to-use music player that can change the beat of any song to match your footsteps automatically.

Awesome idea. Exceptional execution. And a great user interface. Completely worth the price and highly recommended. (iTunes review)

How it Works
– You pick a song to start off with, and in seconds, TrailMix will have determined its exact tempo
– The pace of your footsteps is automatically detected using the accelerometer sensor built into your device
– TrailMix remixes the song to match your current pace by making the tempo faster or slower as necessary
Read more about how TrailMix works.

Amazingly Fun to Use
TrailMix is for everyone, not just workout enthusiasts, because it makes even a casual walk into a delightful experience. Step in sync with the music and brighten your day as you:
– walk to school or work
– stroll to a nearby store or restaurant
– explore a park or beach

Upgrade Your Workout
Of course if you do work out, then TrailMix will take your workout to a whole new level. You’ll experience a rush as you move with the music that lets you break through the mental barrier and perform at your physical peak. According to scientific research, “synchronizing movements with music enables athletes to perform more efficiently, resulting in greater endurance.”

Karageorghis, C., & Priest, D. (2008). Music in Sport and Exercise: An Update on Research and Application. The Sport Journal.

Read more about the benefits of using TrailMix.

Although TrailMix includes an automatic pace detector that works in your pocket or armband, it’s also possible to set the pace manually. This allows you to work out at a single consistent pace with your mobile device placed anywhere on your person.

It Just Works
Our remarkably sensitive pace detector works with the device in either a pocket or armband, regardless of whether you’re running, strolling, or using an elliptical machine or treadmill. And if you speed up or slow down, TrailMix will instantly change the tempo of your music without changing the pitch, making it sound like your songs were originally produced at whatever your current pace happens to be.

TrailMix works without any setup or desktop application thanks to the built-in tempo analyzer that finds the BPM of virtually any song within seconds. We custom-designed our algorithm exclusively for TrailMix for ultra-fast yet incredibly reliable analysis that blows away the competition.
Read more about the tempo analyzer.

Key Features
– Automatically detects your pace when in a pocket or armband.
– Constantly adjusts whatever’s playing to match your current pace without altering its pitch.
– Truly magical. You won’t believe your ears.


Tempo Adjust
TrailMix changes the tempo of any song to match your pace. This feature works just like magic.
Read more about tempo adjustment.

Magic Shuffle
Magic Shuffle selects music of a relatively close BPM to your current pace. This feature is available only in the Pro version.
Read more about Magic Shuffle.

Got Beats?
TrailMix includes an automatic beat detector that lets you use TrailMix on all your favorite songs, no matter what genre you listen to. The beat detector runs in the background, so your music plays instantly with no loading times.
Read more about beat detection.

Follow My Footsteps
TrailMix tracks the pace of your footsteps using your device’s built-in accelerometer sensor. Just slip your iPhone or iPod Touch into your pocket, armband, or backpack, and hit the trail.
Read more about step tracking.

Dial It In
TrailMix features a “cruise control” mode that turns off step tracking and lets you set your own custom tempo instead. This feature is available only in our Pro version.
Read more about cruise control.

High Fidelity
TrailMix changes the speed of your music without distorting the pitch using Dirac mobile, a high-end tempo manipulation library.
Read more about tempo manipulation.

Pocket Friendly
TrailMix features large buttons that are easy to press while on the go.
Read more about the UI design.

Technical Specifications

Audio playback

Supported audio formats: AAC, Purchased AAC (from iTunes store), MP3, Apple Lossless, AIFF, and WAV.



Compatible with all headphones. Controllable using Apple Earphones with Remote.


BPM Accuracy

Accurate to within one two-hundredth of a beat per minute (±0.005 BPM).



Device Support

To use TrailMix, you’ll need either an iPhone 3GS, 4, 4S, 5, 5c, or 5s; or an iPod touch, 3rd, 4th, or 5th generation. Earlier device models are not supported.

Interested in an Android version?

iOS support

TrailMix requires iOS 4.1 or later, and will not run on earlier versions of iOS. Using the latest version of iOS and staying up-to-date is recommended to access all of the newest features.


TrailMix Pro is the world’s best step-synced music player. Available for purchase on the App Store.

TrailMix Pro

TrailMix Pro
Download TrailMix Pro on the App Store

The Pro version features Magic Shuffle, Cruise Control, enhanced stats, unlimited playlist capacity, and no ads. Learn more.

We also offer a discounted classic version.


Download TrailMix on the App Store


Learn how to use TrailMix by reading our introductory guide.


TrailMix was featured in the Seattle Times blog on January 16, 2013 with an article by Mónica Guzmán.

Brothers James and Tom Potter, originally from Issaquah, have created an app called TrailMix that makes the songs on your iPhone or iPod match the tempo of your run or jog. Select a playlist through the app and it will automatically find tracks that match the speed of your steps. Play individual tracks and it will speed up or slow down the songs according to your rhythm.

We also had an article written about us on the AIAIAI blog on January 29, 2013: The TrailMix App: Run like a DJ.

If you’re a blogger or journalist looking to write a story about TrailMix, contact us here:

We’d be more than happy to give you the inside scoop on the story of TrailMix. We can also provide promo codes and a press kit, at your request.