AUv3 apps are Audio Unit version 3 plugins for iPhone and iPad — synths, drum machines and effects that load inside a host app like GarageBand, Cubasis or AUM, the same way plugins work in a desktop DAW. Instead of a synth being a standalone app you record separately, an AUv3 plugin runs right inside your project, fully integrated and saved with it. This is the feature that turns iOS into a serious music-production platform.
The quick version
AUv3 (Audio Unit v3) is Apple’s plugin standard for iOS and macOS. An AUv3 app is a music app that can also run as a plugin within a compatible host. You buy the app once, and it shows up as an instrument or effect you can add to multiple tracks inside your DAW. Note: AUv3 is an Apple format, so it is iOS/iPadOS (and macOS) only — Android does not use it.
How AUv3 plugins work
In desktop music software, you load plugins (VST or AU) inside your DAW. AUv3 brings that same model to mobile. When you add an AUv3 instrument to a track in your host app, the plugin’s interface opens inside the host, you play and record it directly, and its settings save with the project. You can run several instances at once — a Moog synth on one track, a drum app on another, an effect on a third — all in a single session.
This matters because before AUv3, you often had to render a synth app to audio and import it manually. Now everything stays live and editable, which is far closer to how a computer-based studio works.
The three types of AUv3 apps
- Instruments — synths, samplers and drum machines you play via MIDI. Examples include Moog’s Model 15 and Animoog, and Korg’s iMS-20.
- Effects — reverbs, delays, EQs, compressors and creative processors you place on a track.
- MIDI effects — arpeggiators, sequencers and chord tools that generate or transform notes.
For sound choices, our roundups of the best synth apps for iOS and drum machine apps highlight many that ship as AUv3, and adding effects in mobile music apps covers the effect side.
What you need to use AUv3 apps
Two things: an AUv3 host and at least one AUv3 plugin. Common hosts include:
- GarageBand — free and beginner-friendly, supports AUv3 instruments and effects.
- Cubasis — a full mobile DAW with deep AUv3 support.
- AUM — an audio mixer and host popular for live and modular-style setups; see how to use AUM.
- FL Studio Mobile and others — increasingly support hosting plugins too.
If you are choosing a host, our look at the best mobile DAWs compares them.
How to load an AUv3 plugin
- Install the AUv3 app from the App Store (it appears as a normal app).
- Open your host DAW and add a new track or an effect slot.
- Choose to add an Audio Unit / AUv3 instrument or effect, then pick the plugin from the list.
- The plugin’s interface opens inside the host — play, tweak and record as part of your project.
Pair an AUv3 synth with a hardware controller for real playability; see how to connect a MIDI keyboard to your phone.
How to choose AUv3 apps that are worth it
The App Store lists hundreds of music apps, and not all of them are equally useful inside a project. A few practical checks help you spend wisely and avoid clutter:
- Confirm it actually runs as AUv3. Some apps are standalone only. Look for “AUv3” or “Audio Unit” in the description, or test by adding it inside your host before relying on it in a real session.
- Check it does something your host cannot. Most DAWs already include basic EQ, reverb and a sampler. Buy third-party AUv3 apps for sounds and processing your host lacks — a distinctive synth engine, a characterful compressor, or a granular effect, for example.
- Mind the CPU. Big polyphonic synths and convolution reverbs are heavy. On older devices, running many instances can cause crackles or dropouts, so favour leaner plugins or freeze tracks you have finished.
- Look for state saving and presets. A well-built AUv3 recalls its settings perfectly when you reopen the project and ships with usable presets so you are productive straight away.
- Read recent reviews. AUv3 stability depends on how well the developer keeps up with iOS updates. An app that was great two years ago but is no longer maintained can misbehave in a current host.
When you are starting out, a small, dependable set — one good synth, one drum app and a couple of effects — beats a folder full of impulse buys you never load.
Common mistakes to avoid
Most AUv3 frustration comes from a handful of avoidable issues:
- Expecting a standalone app to host plugins. The plugin and the host are separate roles. You still need a host like GarageBand, Cubasis or AUM to load AUv3 instruments and effects into a project.
- Overloading a single session. Stacking many CPU-hungry instances at once is the usual cause of glitching audio. Bounce or freeze tracks as you go to free up headroom.
- Forgetting to save inside the host. Plugin settings live with the host project. If you tweak a synth but do not save the host session, those changes can be lost.
- Ignoring buffer settings. A very low buffer reduces latency but strains the CPU; a higher buffer is more stable for mixing. Adjust it in your host to match what you are doing.
AUv3 vs. standalone vs. Audiobus/IAA
Older approaches like Inter-App Audio (IAA) and Audiobus let separate apps pass audio to each other, but AUv3 is more modern and integrated because the plugin lives inside the host and saves with the project. Audiobus is still useful for routing audio and MIDI between apps, and many producers use it alongside AUv3 rather than instead of it. A standalone app simply runs on its own with no host.
Why AUv3 makes iOS music production powerful
With AUv3, an iPad can run a full session of soft synths and effects inside one DAW, recall it perfectly, and keep everything editable — much like a laptop studio. It is a big part of the answer to whether you can make professional music on a phone, and it is a major reason the iPad is a favourite for mobile producers, as covered in the best tablets for music production.
Frequently asked questions
Are AUv3 apps available on Android?
No. AUv3 (Audio Unit v3) is Apple’s plugin format for iOS, iPadOS and macOS, so it is an iPhone and iPad feature. Android uses different approaches, and apps there typically run standalone or share audio in other ways.
Do I have to pay for AUv3 apps separately?
Each AUv3 app is its own purchase or download, just like any app. Once installed, it can run both standalone and as a plugin inside any compatible host, so one purchase works across all your AUv3 DAWs.
What host app should a beginner start with?
GarageBand is the easiest free starting point and supports AUv3 instruments and effects. As you grow, Cubasis offers a deeper DAW experience, and AUM is great for flexible routing and live setups. Try GarageBand first, then expand.
Why is my AUv3 plugin crackling or dropping out?
This is almost always a CPU or buffer issue. Try running fewer instances at once, raising the audio buffer size in your host, and freezing or bouncing tracks you have finished. Closing background apps and keeping iOS and the plugin updated also helps stability.
Can I use the same AUv3 app in more than one DAW?
Yes. Because the plugin is installed system-wide, any compatible host on your device can load it. A synth you bought for GarageBand will also appear inside Cubasis, AUM or FL Studio Mobile, with its own settings saved per project.
