# Pentatone — Arithmophone Synthesizer AUv3 > Expressive pentatonic keyboard and synthesizer app for music creation and exploration. (iPhone/iPad app by Chiel Zwinkels.) - Source: https://appshunter.io/ios/app/pentatone/id6757822197 (this page in markdown: same URL + `.md`) - Developer: [Chiel Zwinkels](https://appshunter.io/developer/1869126511) - Category: Music, Education - Price: Free - Rating: 5.00/5 from 13 App Store ratings · 3 written reviews indexed - Age rating: 4+ - Requires: iOS 15.6 · 16 MB - Languages: American English, French (France), German (Germany), Japanese, European Spanish - Released: 2026-05-27 - Data updated: 2026-08-27 - Monetization: free - User reviews in markdown: https://appshunter.io/ios/app/pentatone/id6757822197/reviews.md ## What is Pentatone? "Beautiful, fun and inspiringly expressive" - The Arithmophone Pentatone is a music app featuring an easy to play pentatonic keyboard and a built-in synthesizer. Instead of using piano keys or a grid-based interface, Pentatone takes a fresh approach, optimised for the ergonomics of touchscreen devices and inspired by instruments like the kora and mbira. The app also has a sophisticated scale selection system that includes all the common pentatonic scale types and unlocks some more unusual ones. Pentatone features: - An easy-to-play and 'strummable' keyboard, split for two handed playing - An original pentatonic scale system with 9 selectable scales, in just intonation or standard tuning - A custom synth engine (binaural 2x2 op FM with stereo detune, resonant filter, delay and reverb) - 25 preset sounds with macro sliders for tone and ambience - Initial touch and aftertouch response, both polyphonic - AUv3 functionality for use within host apps like GarageBand, Koala Sampler and Loopy Pro Pentatone user feedback: "Amazing! Love the simple UI and the musical keyboard. Also the sounds are lovely!" "This is very cool - beautiful interface and instantly musical." "This really is a joy to play and the tones are really expressive in fun ways that invite different types of creativity." "This app is such a brilliant idea!" "This is amazing. So fun to play. So easy to play with my daughter and my niece. The tones are wonderful." "This is an inspiringly expressive instrument! Really a joy to interact with." "This thing is AWESOME! It’s so easy to make up new stuff with it!" *** Pentatone is part of the Arithmophone project An Arithmophone is a thing that turns numbers into sounds, or math into music. Its name is derived from the ancient Greek words arithmos (number) and phone (sound). Any iPhone or iPad is itself an Arithmophone, because it routinely turns lists of binary numbers into sounds, for example when you use it to listen to music. But this app is a bit more 'arithmophonic' still, because it takes pure and simple harmonic ratios like 3:2 and 5:4 and uses these to build musical scales. You can use it as an easy-to-play instrument, a source of melodic and harmonic inspiration or a tool for learning about music and exploring the deep connection it has with numbers. Keep an eye out, future plans for the Arithmophone on iOS include: - PENTATONE JR., a simplified and text-free version of Pentatone, optimized for young/beginning musicians - DIATONE, the diatonic companion to Pentatone, featuring a 7-note-per-octave keyboard with all the familiar major and minor scales and modes - MIDI / MPE versions of Pentatone and Diatone - TONEHIVE, a microtonal keyboard synth for 7 limit just intonation - HUYGENS, a microtonal keyboard synth for 31 EDO To stay posted, join the community at reddit.com/r/arithmophone or subscribe to the Arithmophone youtube channel: https://www.youtube.com/@arithmophone ## Key features - Easy-to-play 'strummable' pentatonic keyboard - 9 selectable pentatonic scales - Custom FM synthesizer engine - 25 preset sounds with macro controls - Polyphonic touch and aftertouch response - AUv3 functionality for host apps ## Recent user reviews (3 of 3) All indexed reviews: https://appshunter.io/ios/app/pentatone/id6757822197/reviews.md ### 5/5 — Fun,and educational *2026-07-15* Aside from the fact that this is an usually fun app to just bang on, I’ve been using it to solidify the pentatonic scales this app uses on my main instrument. Crazy fun no matter what, and several of the patches sound incredible as a stand alone instrument. It kept me up late last night just creating ambient sounds. Make sure to engage the bend mode, by combining notes and bending one or the other, or both you can achieve some wild tonality. Nice job! **Developer response:** Thanks for all the kind words! Good to hear you're pushing the envelope on Pentatone :) ### 5/5 — Wicked *2026-06-12* I have been really loving playing with this. It’s been really creatively inspiring! **Developer response:** Thank you very much! Great to hear I was able to provide some inspiration :) ### 5/5 — Beautiful tones and fun *2026-06-04* I have way more fun with this app than I ever would have expected. It's just a pleasure to tap progressions and combinations out. No planning or complexity. Just playing music for fun. I hope we see more like this app from the dev in the future. **Developer response:** Thank you so much for your kind words, I'm glad you're having fun making music, that is the main intention behind this design :) More Arithmophonic music apps are definitely coming in the future! ## Frequently asked questions about Pentatone ### What is Pentatone? Pentatone is a music app featuring an easy-to-play pentatonic keyboard and a built-in synthesizer. It offers a unique approach to music creation optimized for touchscreens and inspired by traditional instruments. ### What kind of scales does Pentatone offer? Pentatone features an original pentatonic scale system with 9 selectable scales. These scales are available in both just intonation and standard tuning. ### Can Pentatone be used with other music apps? Yes, Pentatone supports AUv3 functionality, allowing it to be used within host apps like GarageBand, Koala Sampler, and Loopy Pro. ### What kind of sounds can Pentatone produce? Pentatone includes a custom synth engine with binaural 2x2 op FM synthesis, a resonant filter, delay, and reverb. It comes with 25 preset sounds and macro sliders for tone and ambience. ### Is Pentatone suitable for beginners? Users describe Pentatone as 'easy to play' and 'instantly musical,' suggesting it is accessible for beginners. The app is also planning a simplified version called PENTATONE JR. for young/beginning musicians. ### What devices does Pentatone support? Pentatone is available for iPhone, iPad, and iPod. It is designed with ergonomics optimized for touchscreen devices. ### How often is Pentatone updated? The app was last updated on July 13, 2026, indicating recent development activity. Future plans for the Arithmophone project, including new app versions, are also in the works. ### Does Pentatone have ads? No, Pentatone does not contain advertisements. It is a free application with no in-app purchases or ads. ## Version history (last 3 releases) ### 1.1.1 — 2026-08-11 Version 1.1.1 adds the ability to run multiple instances of Pentatone simultaneously within an AUv3 host. Also: added 30 Hz highpass filter to prevent low frequency rumble, and made some improvements to the guide text. ### 1.1 — 2026-07-13 - Waterfall keys: the keyboard is now 'strummable' so you can play multiple notes by sliding your finger across the keys - AUv3 functionality: Pentatone now works within host apps like GarageBand, Loopy Pro and Koala Sampler, so you can record its output as audio and/or midi. ### 1.0 — 2026-05-27 No release notes. ## More apps by Chiel Zwinkels - [TernaryClock](https://appshunter.io/ios/app/ternaryclock/id6761714021) All apps by Chiel Zwinkels: https://appshunter.io/developer/1869126511 ## Related topics [pentaton](https://appshunter.io/ios/topics/pentaton) · [pentatone](https://appshunter.io/ios/topics/pentatone) · [pentatonic](https://appshunter.io/ios/topics/pentatonic) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-27.*