Comparison

iDousyn vs Rainbow Keys

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

iDousyn

This app transforms your device into a professional music production tool. It features a sample-based synthesizer with dual-layer sampling, advanced filters, and a professional effects chain. Create immersive sounds and build captivating tracks with an intuitive interface and extensive sound library.

Highlights
  • Dual-layer sampling
  • Advanced filters and EQ
  • Professional effects chain
  • Creative chord pads
  • MIDI mastery
  • Expansive sound library
Features
Read full description

iDousyn transforms your iPhone and iPad into a premium sampler, synthesizer, and AUv3 plugin built for professional music production, beat making, and sound design. Powered by a massive dual-layer rompler engine, it delivers a touch-optimized workflow to create studio-quality music anywhere. Seamlessly integrating as a high-performance AUv3 Audio Unit, iDousyn is the perfect companion for Logic Pro for iPad, GarageBand, Cubasis, AUM, Loopy Pro, and other leading iOS DAWs. Whether you are producing EDM, making hip hop beats, scoring cinematic soundtracks, or designing ambient soundscapes, iDousyn gives you the ultimate sonic palette. Chord Sequencer & Harmony Engine • Ultimate Inspiration: Instantly browse, audition, and map over 432 chord variations and 100 global musical scales directly to your pads—no advanced music theory required. • Timeline Sequencer: Drag and drop your custom chords into the new visual timeline. Program rests, set loop lengths, and let the zero-latency lookahead scheduler play your progressions with perfect tempo synchronization. • Dynamic Performance: 10 customizable Chord Pads featuring intelligent strumming, dual MIDI keyboards, and assignable key ranges with real-time Neon Glow visual feedback. Dual-Layer Synthesis & DSP Effects • True Dual-Layer Rompler: Stack and blend two independent sample oscillators. Fine-tune with octave, semitone, cents, pan, and level controls for massive, evolving textures. • Studio-Grade FX Chain: Shape your tone with multi-mode filters, a parametric EQ, and fully automatable AUv3 effects including Reverb, Delay, Chorus, Flanger, Phaser, Compressor, and Limiter. Massive Sound Library & iCloud Sync • 1,100+ Premium Samples: An expansive built-in soundbank featuring heavy basses, lush synth pads, sharp leads, drum kits, acoustic guitars, and orchestral strings. • Smart Presets: Create unlimited custom patches. Your library is safely backed up with automatic, silent background iCloud Drive synchronization across all your Apple devices. Pro Recording & Export • Lossless Audio & MIDI: Record your live sessions directly within the app and export high-fidelity FLAC, WAV, AIFF, CAF, or M4A audio files, as well as full MIDI sequences. • AudioShare Integration: Instantly route your bounces to your favorite audio editors. • Background Audio: Keep your sequences running and your MIDI controllers active even while switching between apps. Designed for modern producers, beat makers, live performers, and synth enthusiasts, iDousyn brings desktop-class virtual instruments right to your fingertips.

About

Rainbow Keys

Learn piano scales and chords with augmented reality. This app overlays key names onto your keyboard, aiding real-time learning for improvisation and music theory.

Highlights
  • Augmented reality key display
  • Object recognition for keyboards
  • Selectable scales and chords
  • Real-time learning
  • Music theory education
  • Improvisation aid
Read full description

Rainbow keys is an interactive augmented reality app that uses object recognition to display the names of the keys onto your piano or keyboard. You can select from a large range of scales and chords to display, allowing you to learn in real time. It's great for improvisation, developing your skills in piano and learning music theory.

Screenshots

iDousyn4 screens
Rainbow Keys4 screens

Verdict

The call

The clearest difference is review sentiment: Rainbow Keys at 100% against iDousyn's 34%. Rainbow Keys also leads on price (Free vs $3.99) and in-app purchases (none vs 1). On ads, monetization model and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Rainbow Keys is free to download; iDousyn costs $3.99 up front. iDousyn sells 1 one-off in-app purchase. Rainbow Keys asks for nothing beyond the download.

UpkeepUpdate frequency

iDousyn ships an update every 2 months, Rainbow Keys every 4 days. The most recent releases landed on November 10, 2026 and November 4, 2026 respectively.

Scorecard5 real differences · 5 level
iDousyn versus Rainbow Keys: the parameters behind the verdict, then further details
ParameteriDousynRainbow Keys
Price$3.99Free — better
Rating4.2 (161 ratings) — better—
Positive reviews34.1% of reviews100.0% of reviews — better
Number of ratings161 — better—
Update frequencyEvery 2 monthsEvery 4 days — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS26.017 — better
Further details — not scored
Size1.2 GB34 MB
Age rating4+4+
DeveloperJorge LozadaMatthew Sefton

Customer experience

iDousyn

All ratings159 ratings
Positive78.6%
Neutral2.5%
Negative18.9%
Written reviews44 reviews
Positive34.1%
Neutral6.8%
Negative59.1%

Rainbow Keys

Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

iDousyn

Reported bugs

15 issues
  • App crashes immediately
  • Full version displays full-page ads
  • Ads appear on the front page
  • New update has ads
  • Implemented trackers
Show 10 more
  • iDousyn Lite works, this one does not
  • App does not open
  • MIDI input timing issues
  • Sound crash sometimes
  • Long delay between external MIDI and sound
  • Sluggish keyboard
  • Sluggish interface
  • Glide is always on
  • Scrolling menu is hard to use
  • Sliders on scrolling menu

Requested features

10 requests
  • Adaptive Crasher (AUV3, Adaptive Cubasis and Zenbeats)
  • AUV3 support
  • Audiobus compatibility
  • MIDI IN for better keyboard control
  • Background audio option
Show 5 more
  • Reset button
  • Fix sound crash
  • Improve interface contrast
  • Make panel brighter
  • Allow turning off glide

Rainbow Keys

Not enough reviews yet to summarise bugs or requests.

In-app purchases

1 purchases

iDousyn

One-time1
  • Unlock ProFree
None

Rainbow Keys

No in-app purchases

Questions

Is iDousyn free?
iDousyn costs $3.99, and also offers in-app purchases.
Is Rainbow Keys free?
Rainbow Keys is free to download, with no in-app purchases.
Do iDousyn or Rainbow Keys have ads?
Neither iDousyn nor Rainbow Keys shows ads.
Which is updated more often, iDousyn or Rainbow Keys?
iDousyn ships an update every 2 months, and Rainbow Keys every 4 days. Most recently, iDousyn was updated on November 10, 2026 and Rainbow Keys on November 4, 2026.

Other comparisons