AudioStretch:Music Pitch Tool

Review by eFreeware

If you learn music by ear, the hardest part is rarely finding the piece. It is getting a fast passage slow enough to hear clearly, or dragging a recording into a key that matches your instrument. AudioStretch, from BandLab Technologies, is built for exactly that job: it changes the speed of an audio file without touching the pitch, or changes the pitch without touching the speed.

The app is free to install, carries no ads, and offers in-app purchases. It has passed a million installs and holds a 3.5 average across 4,632 ratings, which suggests a tool people reach for regularly rather than a novelty. Released in July 2019 and updated as recently as May 2026, it is pitched at players, students and anyone who wants to pull a part apart note by note.

Slowing a passage without flattening it

The core of the app is independent control of pitch and time. Speed runs from a standstill up to ten times normal, while pitch moves as much as 36 semitones in either direction, with fine tuning down to a single cent. Those two sliders do different jobs: slow a solo down to half speed and the notes stay where they were, or lift a track a couple of semitones to sit under your voice without it turning into a chipmunk impression.

Zero-speed playback is the feature I find most interesting. You can set the speed to nothing, or press and hold on the waveform, and the app plays the specific note under your finger. That turns a dense chord or a quick lick into something you can examine one sound at a time, which is a different exercise from looping a phrase and hoping your ear catches up.

LiveScrub extends the same idea. Audio plays as you drag or hold the waveform, so you can move through a recording at your own pace and hear what sits at each point. For transcription work, where you are writing down what you hear rather than just copying it, that kind of control is more useful than a simple play button.

Markers, loops and moving files around

Longer pieces need navigation, and the app handles this with markers. You can set as many as you like to jump between the sections that matter, or to bookmark a spot you want to come back to. A flexible A-B loop sits alongside them, letting you isolate the bars you are working on and repeat them until they stick.

Audio comes in from several places. You can pull files from your music library, from device storage, or from cloud storage such as Google Drive, Dropbox or OneDrive. If your phone has a default audio recorder installed, the app can capture audio through it, which covers the case where you want to work on your own playing rather than a released track.

Export works the other way. Once you have set a pitch or speed you like, you can write the adjusted audio out as a file and save it to your device or send it to cloud storage. That makes the app useful beyond practice sessions: you can prepare a slowed-down version of something to carry with you, or produce a pitch-shifted file to hand to someone else.

What you need before you start

There is not much to set up. The app works with audio you already have or can reach, so the practical requirement is a file to open and somewhere to keep it. Importing from cloud storage means fetching something from Drive, Dropbox or OneDrive, while files already on the device are simply there.

The one clear limitation is video. The developer notes that video playback is not part of the Android version, in either the free or paid release, so the app is an audio tool on this platform. If your reference material is a video lesson, you would be working from its audio instead.

The developer describes the app as award-winning and calls it responsive and easy to use. The controls are the kind you can understand without a manual, even if getting a clean transcription out of a difficult recording still takes patience.

Players who get the most from it

This is a tool for people who work on music rather than simply listen to it. Guitarists and bassists picking out riffs, pianists learning voicings, singers working out a melody line, students preparing a piece for a lesson, and anyone transcribing a solo for writing or teaching all fit the same mold. The combination of pitch shifting, speed control and markers maps onto the way that work actually happens.

It also suits players who want to experiment. The pitch range is wide enough to move a track into a different register entirely, and the speed range runs all the way to ten times normal, which is more than practice requires. Someone curious about how a familiar song sounds stretched or dropped will find plenty to poke at.

The 3.5 average is worth reading plainly. It is a middling score from a large enough group of ratings to mean something, and it suggests the app does its job for many users without delighting all of them. The absence of ads is a point in its favor for anyone who has used practice tools that interrupt the work.

A focused tool for learning by ear

AudioStretch does one thing and does it in depth: it gives you control over the pitch and speed of an audio file so you can hear what is going on inside it. LiveScrub, zero-speed playback, unlimited markers and A-B looping are all variations on that single purpose, and they are the reasons to install it rather than reach for a general music player.

The free download and the in-app purchases make it easy to try. The Android version leaves video out, so it is audio only on this platform, and the 3.5 rating suggests you should expect a capable tool rather than a flawless one. If your goal is to learn parts by ear, transcribe what you hear, or hear a familiar track from a new angle, this is a sensible place to start.

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