Comparison

Core Synth Free vs Retro Synth

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

Head to head
About

Core Synth Free

Create music with a monophonic synthesizer featuring dual oscillators, adjustable filters, and envelope shaping. Explore various wave patterns and octaves to craft unique sounds for live performance or composition.

Highlights
  • Dual overlapping oscillators
  • Four wave patterns
  • Adjustable low pass filter
  • ADSR envelope shaping
  • 1 octave keyboard
  • Save and load patches
Features
Read full description

Get your groove on with Core Synth Free, the definitive monophonic synthesizer for the iPhone and iPod touch. With tons of features packed into a small package, Core Synth is great for live performing. This free app has the following features: - 1 Octave keyboard - Keys light up in different colors when pressed Oscillator Module - Dual overlapping oscillators - Four wave patterns: Square, Triangle, Sawtooth and Reverse Sawtooth * Select from 5 octaves * Adjust glide between notes * Fine tune Oscillator 2 with option to sync with Oscillator 1 Volume Envelope Shaper - Edit ADSR (Attack, Decay, Sustain, Release) Low Pass Filter Module - Adjust Cutoff and Resonance - Edit ADSR (Attack, Decay, Sustain, Release) Upgrade to the full version within the app for the following additional features: - 7 Octave Keyboard - Octave control to move along entire range Patches Module - Save an unlimited number of individually named patches - Browse through your collection before applying patch - Delete unwanted patches - Backup patches via iTunes File Sharing Modulation Module - Four wave patterns: Square, Triangle, Sawtooth and Reverse Sawtooth - Modulate Filter, Pitch or Wave - Adjust LFO Rate and amount Arpeggiator Module - Arpeggio moves up to 5 octaves - Four step modes: Up, Down, Up/Down, Random - Adjust rate Many more exciting enhancements to follow! Core Synth Free includes open source code from MobileSynth developed by Allen Porter.

About

Retro Synth

Create authentic retro music with this vintage-inspired synthesizer app. Explore sound design with tone controls and vibrato, or upgrade for premium waveforms and studio effects. Designed for instant musical creativity, it offers a portable music-making experience.

Highlights
  • Authentic vintage sound recreation
  • Tone control for sound shaping
  • Vibrato effect for musical expression
  • Zero latency real-time response
  • Premium waveforms (Sine, Sawtooth, Triangle)
  • Studio effects (Reverb, Delay)
  • MIDI export
Features
Read full description

Play a real pocket stylophone — then plug it straight into GarageBand. Retro Synth · Syntophone turns your device into a vintage touch-keyboard synthesizer, and now works as an AUv3 instrument inside GarageBand, Logic Pro, and AUM. Slide your finger across the keys and a warm, authentic square-wave synth comes to life. Learn built-in songs with light-up "follow the key" tutorials, record your ideas, and drop the instrument into your favorite music app — all from one tiny synth. Like the original, it plays one note at a time: one stylus, one note. Curious about Pro? Tap any locked sound and hear it free for 30 seconds. FREE FEATURES (Included at no cost): • Authentic Vintage Sound: faithfully recreates that iconic square-wave tone with modern precision. • Song Mode: learn songs with light-up "follow the key" tutorials, hold-to-repeat for repeated notes, and a star rating when you finish (2 songs free). • My Recordings: a full library to play back, rename, share, and delete your takes. • Metronome: a sample-accurate click with adjustable BPM and an accented downbeat to keep you in time. • AUv3 Instrument: use Syntophone as a plug-in inside GarageBand, Logic Pro, AUM and other AUv3 hosts. • Sound Controls: shape your tone from thin and bright to thick and warm, and add expression with vibrato. • Real-time Response: instant, zero-latency audio as you play. • Clean, minimalist design inspired by vintage hardware. SYNTOPHONE PRO (subscription): Upgrade to unlock the full studio: • Premium Waveforms: Sine, Sawtooth, and Triangle. • Studio Effects: high-quality Reverb and Delay. • Pro Sound Panel: a second detuned oscillator for a fatter analog tone, hands-on delay time & feedback controls, and live MIDI output — play GarageBand and other synth apps as a virtual MIDI keyboard. • 12 more built-in songs to learn. • MIDI Export: save and share your recordings as .mid files. WHY SYNTOPHONE? No setup, no menus to fight — open the app and make music immediately. Then, when you're ready, it becomes a plug-in in your studio. Note: The app includes an auto-renewable subscription (Syntophone Pro) for premium features. For Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Screenshots

Core Synth Free3 screens
Retro Synth4 screens

Verdict

The call

The clearest difference is rating: Retro Synth at 4.2 against Core Synth Free's 2.9. Retro Synth also leads on update cadence (every 2 months vs every 13 months). Core Synth Free's advantage is iOS requirement (8.0 vs 17.0). On price, ratings volume, ads and in-app purchases 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

Both are free to download. Core Synth Free sells 1 one-off in-app purchase and Retro Synth sells 3 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Retro Synth holds the better App Store score, 4.2 against 2.9. Both are backed by a comparable volume of ratings — 8 and 5 respectively.

UpkeepUpdate frequency

Core Synth Free ships an update every 13 months, Retro Synth every 2 months. The most recent releases landed on November 3, 2026 and October 30, 2026 respectively.

Scorecard3 real differences · 7 level
Core Synth Free versus Retro Synth: the parameters behind the verdict, then further details
ParameterCore Synth FreeRetro Synth
PriceFreeFree
Rating2.9 (8 ratings)4.2 (5 ratings) — better
Positive reviews57.5% of reviews—
Number of ratings8 — better5
Update frequencyEvery 13 monthsEvery 2 months — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPodiPhone, iPad
Requires iOS8.0 — better17.0
Further details — not scored
Size7 MB14 MB
Age rating4+4+
DeveloperCore Engine AppsKerem ERSU

Customer experience

Core Synth Free

All ratings8 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews87 reviews
Positive57.5%
Neutral12.6%
Negative29.9%

Retro Synth

All ratings5 ratings
Positive80.0%
Neutral0.0%
Negative20.0%

In-app purchases

1 purchases

Core Synth Free

One-time1
  • Full Version Upgrade$0.99
3 purchases

Retro Synth

Subscriptions2
  • Monthly Subscription$3.991 Month
  • Annual Subscription$24.991 Year
One-time1
  • Remove ads$2.99

Questions

Is Core Synth Free free?
Core Synth Free is free to download, with in-app purchases available.
Is Retro Synth free?
Retro Synth is free to download, with in-app purchases available.
Which has better reviews, Core Synth Free or Retro Synth?
Retro Synth is rated higher. Core Synth Free averages 2.9 out of 5 from 8 ratings, while Retro Synth averages 4.2 from 5 ratings.
Do Core Synth Free or Retro Synth have ads?
Neither Core Synth Free nor Retro Synth shows ads.
Which is updated more often, Core Synth Free or Retro Synth?
Core Synth Free ships an update every 13 months, and Retro Synth every 2 months. Most recently, Core Synth Free was updated on November 3, 2026 and Retro Synth on October 30, 2026.

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