Frequently Asked Questions

Prospero works on any iPhone or iPad running iOS 16 or later. For the best tracking accuracy, a device with a Face ID TrueDepth camera (iPhone X or later) or a LiDAR Scanner (iPhone 12 Pro and later) is recommended — both provide depth data that improves hand-position precision.

There is a simple synthesizer built in to Prospero that provides instant feedback, but there is also a MIDI mode that turns your phone into a hands-free instrument controller, either external or on the same device.

If you want to run MIDI mode on the same device, you will also need a MIDI-compatible synthesizer app running alongside Prospero. Popular iOS-based free options include:

• GarageBand (free, Apple) — select any instrument and set Prospero as the MIDI input
• AudioKit Synth One J6 (free, open source) — a full-featured synth with rich MIDI support
• AUM — for professional setups

If you’re not hearing any sound in Prospero, verify the following things.

• Prospero’s AUDIO mode uses whatever iOS audio mode is active. Verify there are no bluetooth devices connected and your system audio is audible.
• If using camera mode, make sure your hand (or hands, if you have Prospero Pro) are at least 12-18 inches away from the camera. You should see a yellow dot appear on the screen to represent where your hands are being detected. (The motion tracker actually identifies and tracks your wrist.) If you’re still having trouble, try moving to a different background, and make sure there is plenty of light. You might get better results moving even further back from the phone.
• If you are still not seeing any yellow dots, you may not have enabled camera access. Go to Settings > Apps > Prospero and toggle Camera. We will never ever view or save your camera data - it is not saved, and never leaves your phone.

MIDI mode is the gateway to an incredibly powerful network of music routing. MIDI carries information, not audio - so if you switch to MIDI mode, you need something else to generate the audio based on the digital information being received from Prospero. This might be synthesizer app running in the background on the same device, or another device connected via a cable. The options are truly endless.

We will never ever save your camera information - in fact, it is not recorded in any way, shape, or form by Prospero. We use the camera, via Apple’s Vision library, to execute real-time motion tracking.

Free gives you one-hand tracking over the pentatonic scale — a fully functional instrument, forever free. Includes both MIDI and Audio modes, the built-in mono synth, and per-pitch aftertouch.

Pro ($17.99 $6.99 early bird discount) adds up to four simultaneous signals, scale and key selection (chromatic, pentatonic, modal, and more), advanced synth controls: glide/portamento and attack/release envelope shaping, more synth waveforms, and audio effects like fuzz, delay, and reverb.

Creator (coming soon) is the full instrument: body and face tracking, custom MIDI CC mapping, and session storage with MIDI export. Currently in development.

Yes — Prospero outputs standard CoreMIDI, which you can route to hardware synths in two ways:

Network MIDI (wireless): Connect your device to the same Wi-Fi network, open Audio MIDI Setup, and create a Network MIDI session. A Mac or other iOS device can then bridge MIDI to any USB hardware synth. (Note - this is handled outside Prospero. If Prospero is in MIDI mode, it will send MIDI output on whichever channel is selected in the settings.)

USB/Lightning MIDI Interface (wired): Connect a class-compliant USB MIDI interface (such as an iRig MIDI 2 or Roland UM-ONE mk2) to your iPhone’s Lightning or USB-C port. Prospero will send MIDI signals along this pathway.

iOS 16.0 or later is required for the core hand-tracking features. An iPhone Pro 16+ or iPad Pro is recommended for best results.

Always keep your iPhone updated for the best experience.

The Free tier is always free — no credit card required, no time limit. You get single-hand chromatic tracking and audio creation indefinitely.

Pro and Creator subscriptions each include a 7-day free trial for new subscribers. You can cancel at any time before the trial ends and will not be charged. Subscriptions are managed through your Apple ID in the App Store.