Free online tool

Slowed Reverb for Android

Make slowed + reverb edits on Android in Chrome. Pick a song from Downloads or Files, set speed, reverb and bass, save an MP3 to your phone. Free, no app.

Open the free editor: upload MP3, WAV, AAC, OGG or FLAC, adjust speed, reverb, bass, tone, width and space, then export MP3 or a ZIP of many tracks. Everything runs in your browser.

You can make a slowed reverb edit on an Android phone with nothing but Chrome and a song file. The editor above runs inside the browser, decodes your file on the phone, processes it on the phone and saves the MP3 to the phone. There is no APK to sideload, no Play Store listing to find, and no account. This page covers the Android-specific parts: where to find your files, where the export lands, and what to expect from processing time and battery.

The general controls are the same as on every other device. If you want the full explanation of speed, reverb, bass and the rest, the slowed reverb maker page has it. The app page compares this editor to the apps you will find in the Play Store. And if you are on an iPhone instead, the iPhone page covers Safari.

One thing to clear up early: the Slow & Reverb for YouTube Chrome extension does not run on Android. Chrome for Android does not support extensions. On an Android phone, this editor and your own audio files are the way to get the sound.

Picking a file on Android

Tap the editor's file area. Chrome opens the Android system file picker, which is the same picker the Files app uses. From there:

• Recent shows files you touched recently, which is often the fastest route to a song you just downloaded.
• Downloads is where browser downloads and most messaging app saves end up.
• Audio filters to audio files across the device.
• The hamburger menu or side panel lists storage locations, including the internal storage, an SD card if you have one, and cloud providers like Google Drive if their apps are installed. Files from Drive are downloaded to the phone first, then handed to the browser, so they still process locally.

Long press to select more than one file if you want a batch. The editor accepts MP3, WAV, AAC, OGG and FLAC, plus anything else Chrome can decode. Some file managers hide the Audio filter and show everything; that is fine, just browse to the folder.

If a song lives inside another app, such as a music player's private folder, the system picker usually cannot see it. Share it from that app to Files, or save it to Downloads, then pick it from there.

Where the exported MP3 goes

When you tap download, Chrome saves yourfile-remix.mp3 to its downloads folder. By default that is the Download folder on internal storage. A notification appears when the save finishes, and tapping it opens the file in whatever app handles audio on your phone.

To find it later, open the Files app (or Files by Google, or your manufacturer's file manager) and look in Downloads. Chrome also lists it under its own menu at Downloads. If you have changed Chrome's download location in Settings, Downloads to an SD card or to ask every time, the file goes wherever you pointed it.

A batch export is a single ZIP, all-remixes.zip or selected-remixes.zip. Android's Files app can open ZIPs and extract them in place, so you do not need another app to get at the MP3s inside.

To share the result to a video editor, a messaging app or a cloud drive, long press the file in Files and tap Share, or open it from the Chrome download notification and share from there.

Processing time and battery

Phones process slower than laptops, and this editor does real work: it decodes the whole file, runs it through the effect chain, then encodes an MP3 in a web worker. On a recent Android phone a single song is a short wait. On an older or budget phone it is a longer wait, and a long file or a batch stretches it further.

Two Android behaviours matter here:

1. Chrome throttles background tabs. If you switch to another app or lock the screen while a render is running, Android may slow or pause the tab. Keep Chrome in front with the screen on until the download notification appears. For a batch, that can mean leaving the phone alone for a while.
2. Battery saver and adaptive battery can limit CPU for apps they consider background. If a long batch keeps stalling, plug the phone in and turn battery saver off for the duration.

Battery use is real but bounded. The work is CPU-bound, so a few songs cost a small slice of charge. A full album batch is better done plugged in. The processing itself does not use mobile data, because nothing is uploaded; the only network use is loading the page.

If you own a laptop as well, do batches there and use the phone for quick edits. The bulk converter page explains how batch sizes interact with memory on either device.

Settings that sound right on phone speakers

Slowed edits made on headphones often collapse when played back on a phone speaker: the heavy bass vanishes, and wide stereo thins out. Since you are on a phone, check on its speaker before you post. These starting points are safer on small speakers than the default presets.

Width at 1.0 keeps the mix as it was recorded, which is the safe choice when the main listener is also on a phone. Push it to 1.2 or 1.3 only for headphone-first uploads.

Add the editor to your home screen

Open slowandreverb.com in Chrome, tap the three-dot menu, then Add to Home screen or Install app, depending on your Chrome version. Confirm, and you get an icon that opens straight into the editor without the address bar. It is still the website, so updates arrive automatically and nothing extra is stored beyond the icon and a cached copy of the page.

Custom presets you save with Create preset live in Chrome's local storage on this phone. They persist between visits, including when launched from the home screen icon, but they do not follow you to another device.

Other Android browsers

Samsung Internet, Firefox for Android, Brave and Edge all include the Web Audio API and run the editor. Chrome is the most tested, so if something behaves oddly in another browser, try the same file in Chrome before assuming the file is the problem. Firefox on Android does support add-ons, but the Slow & Reverb for YouTube extension is a Chrome extension and is not available there; a separate Firefox add-on called Slowverb does the live-YouTube job on desktop Firefox.

What stays the same, and what to expect

Every feature is present on Android. Presets, Preserve pitch, per-track settings via selection, ZIP batch export, the spectrum visualizer during playback. Export is MP3 at 96 kbps, 32 kHz, the same as on desktop, and there is no WAV option on any device. That bitrate is fine for YouTube, TikTok and Shorts because those services re-encode uploads anyway. For a lossless master, process a WAV source on a computer in a DAW.