SpellSynth vs Retromulator
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
SpellSynth
This app recreates a classic 1978 spelling toy with four engaging game modes. It allows users to type any word or phrase and hear it spoken aloud using vintage synthesized voices. Explore different speech synthesis eras and even play the keypad with a MIDI keyboard.
- Type and hear any word spoken
- Four game modes (Free Play, Spell, Mystery Word, Say It)
- Three distinct vintage voice characters
- MIDI keyboard support
- Export audio to WAV
- Adjustable gap between words
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SpellSynth is a playable love-letter to the 1978 spelling toy that taught a generation to read — rebuilt for iPhone, iPad, and Mac, in English and French, with five modes, a crunchy VFD display, and three vintage voice characters across two decades of speech-synthesis history. Tap a letter and it speaks. Type ANY word — your name, this week's vocabulary list — and SpellSynth speaks it back. EVERY WORD SPEAKS The 500+ bundled words across 20+ themes use a hand-recorded retro voice. Anything else — a name, your kid's spelling list — falls back to the system engine through your chosen voice, cached so the second tap is instant. • FREE PLAY — type any word, a whole phrase, or a number and hear it spoken. Tap SPACE to build a sentence; it's read back word by word as the VFD cycles. Numbers ("2" becomes "two") and contractions ("don't") speak too. A GAP control tunes the pause between words (50–500 ms), and a RECENT row keeps this session. • SEQ — a 16-step sequencer that speaks a word per step, locked to your tempo. Type four words, get a robot vocal loop. Put a single letter on a step and it says the letter name on the beat instead. FIT stretches each word to fill its step, so words pitch up as the tempo climbs. • SPELL — SpellSynth says a word. You spell it. Three mistakes and you get the answer, then try a new one. HINT reveals a letter when you're stuck. • MYSTERY WORD — the classic hidden-word game. You get the category and first letter free; pick letters until it reveals itself. Six wrong guesses ends it. • SAY IT — listen-and-repeat practice. SpellSynth spells the word letter by letter, then says it whole. REPEAT to hear it again, NEXT for a new one. • SHARE — render any word or phrase to a WAV and send it to Files, AirDrop, or your DAW. EN FRANÇAIS Pick Français in Settings and SpellSynth speaks French: 360+ words, French game screens and an apostrophe key, after the 1981 French edition. The AUv3 speaks French too. THREE VINTAGE VOICES Pick a voice character in Settings. Each one draws from a different era of speech-synthesis history, applied to every word you hear: • 1968 ODYSSEY — calm, deep-baritone monotone with a deliberately slow cadence. Aesthetic homage to the late-60s sci-fi AI voices. • 1978 LPC — the original Speak & Spell character. A 10-pole LPC vocoder driven by the actual TMS5220 chirp ROM, the same speech algorithm Texas Instruments shipped in the toy. Buzzy, granular, unmistakable. • 1986 DECTALK STYLE — fixed-pitch impulse train through formants extracted from your input. Modelled on the Klatt-style synthesis that defined Hawking's iconic computer voice. Deliberate, monotone, emphatically computery. • DEFAULT — clean system speech, no extra processing, for when you just want clear pronunciation. PLAY WITH A MIDI KEYBOARD Connect a USB, Bluetooth, or Network MIDI keyboard and the keypad plays from real keys. MIDI notes 60–85 (C4–C#6) trigger letters A–Z. BUNDLED AUDIO UNIT (AUv3) SpellSynth ships an AUv3 instrument extension, so the same voice engine loads inside GarageBand, AUM, Loopy Pro, Cubasis, Logic Pro for iPad, and any AUv3 host on iPhone or iPad. Type a word and it speaks. Twenty-four parameters cover pitch, speed, bit-crush, sample-rate reduction, filter, envelope, LFO, stutter, the step sequencer, MIDI shaping, language, and voice character. Ten factory presets; all four voices play in your DAW. A serious MIDI surface for performers: sustain pedal (CC 64) for hold-and-release phrasing, Channel Pressure (aftertouch) routable to any parameter, three velocity curves (Soft / Linear / Hard), a pitch-bend range from ±0 to ±12 semitones, and 14 MIDI Learn targets covering every performance knob — bound CCs ride along with the preset. Stutter locks to the host tempo (1/4, 1/8, 1/16), and a Letter Map mode maps A–Z onto MIDI notes 60–85 so you can sequence spelling right in your DAW. Perfect for producers chasing that Kraftwerk / Stereolab / Broadcast sound.
Retromulator
This app recreates legendary vintage synthesizers, samplers, and keyboards through accurate emulation. It functions as a standalone application or an AUv3 plugin, offering classic electronic music hardware sounds on iOS devices.
- Cycle-accurate hardware emulation
- AUv3 plugin support
- Standalone app functionality
- Full MIDI control
- ROM firmware loading
- Background audio support
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Retromulator is a multi-core retro hardware emulation app and AUv3 plug-in that brings legendary synthesizer, sampler, and keyboard cores back to life through authentic low-level emulation. Each core runs its actual firmware, physical model, or sample data — delivering the unmistakable character of the hardware that defined electronic music from the early 80s through the 2000s. — EMULATED CORES — VIRTUAL ANALOG SYNTHS Firmware-level chip emulation, enabled with the 56k cores option (requires M1 iPad or iPhone 15 Pro or newer): • Access Virus A, B and C — Motorola DSP 56300 recreation • Access Virus TI / TI2 / Snow — Motorola DSP 56300 recreation • Clavia Nord Lead 2X — Motorola DSP 56300 recreation • Waldorf microQ — Motorola DSP 56300 recreation • Waldorf Microwave XT — Motorola DSP 56300 recreation • Roland JP-8000 and JP-8080 — JE-8086 core by Giulio Zausa ANALOG SYNTHS • Oberheim Matrix-1000 — original firmware on an emulated Motorola 6809 board driving six CEM3396 voice models, with ROM banks 2 to 9 from the patch EPROM, a MIDI CC for each of the 96 patch parameters and LFO sync to the host tempo or MIDI clock FM SYNTHESIS • Yamaha DX7 — original chip set emulation, based on VDX7 by Charles Chiaccona • Yamaha OPL3 — Nuked OPL3 cycle-accurate FM by Nuke.YKT GM / GS SOUND MODULES • 88emu — Roland SC-88, SC-88VL, SC-88Pro, SC-8850 and SC-55mkII boards, emulation by Giulio Zausa, with GS variation, map and rhythm handling, program and drum kit names read straight from the board ROM, 16-part multitimbral operation, and a Standard MIDI File player with offline rendering to WAV or AAC. CHIPTUNE • Commodore 64 SID 6581/8580 — based on reSID. 3-voice polyphony, 8580 chip model with high-quality RESAMPLE, GoatTracker .sng / .ins bank loading (GTS3/4/5, GTI3/4/5) and .sid file import (PSID/RSID), full macro playback engine (wavetable, pulsetable, filtertable, speedtable) and live MIDI control of cutoff (CC 74), resonance (CC 71), pulse width (CC 75), vibrato (CC 1) and pitch bend. • Ayumi (AY-3-8910 / YM2149) — the PSG behind the ZX Spectrum, Amstrad CPC, Atari ST and MSX. Ayumi emulation by Peter Sovietov with the Ym2149Synth voice engine, 3-voice polyphony, switchable AY / YM engine, .ay patch loading, Factory and User banks, and 11 live CC controls. ORGAN • Hammond B3 with Leslie speaker — OpenB3, based on the setBfree engine by Michele Perrone. Upper, lower and pedal drawbars, percussion, vibrato and chorus, overdrive, reverb, three Leslie cabinets, keyboard split and .fxp presets ELECTRIC PIANO AND SAMPLER • Wurlitzer 200A — OpenWurli physical modelling by hal0zer0 (Rust ported to C++ by discoDSP) • Akai S1000 — SFZero sample engine by Steve Folta, with Bliss Sampler support and resampling engine by discoDSP (SF2 / SFZ / ZBP / ZBB) — KEY FEATURES — • Native AUv3 plug-in for AUM, Cubasis, GarageBand, Logic Pro and more • Standalone app for iPhone and iPad • Full MIDI control: CC, mod wheel, expression, pitch bend • 8-point sinc interpolation for sample playback • Auto-slice drum mapping and global retuning via MIDI • ROM firmware loading from original hardware • Background audio, iCloud and Files app integration • Optimised interpreter compatible with the iOS App Store sandbox
Screenshots
Verdict
The clearest difference is price: SpellSynth at $2.99 against Retromulator's $19.99. Retromulator's advantage is chart position (#199 vs unranked) and iOS requirement (15.0 vs 17.0). On review sentiment, update cadence, 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
SpellSynth costs $2.99 and Retromulator $19.99 up front. Neither carries in-app purchases, so what you see is what you pay.
SpellSynth ships an update every 6 days, Retromulator every 3 days. The most recent releases landed on October 19, 2026 and October 18, 2026 respectively.
| Parameter | SpellSynth | Retromulator |
|---|---|---|
| Price | $2.99 — better | $19.99 |
| Rating | 3.2 (11 ratings) — better | — |
| Positive reviews | 50.0% of reviews | 50.0% of reviews |
| Number of ratings | 11 — better | — |
| Update frequency | Every 6 days | Every 3 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Best chart rank | — | #199 — better |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 112 MB | 83 MB |
| Age rating | 4+ | 4+ |
| Developer | Chih Han Lin | DiscoDSP LLC |
Customer experience
SpellSynth
Retromulator
In-app purchases
SpellSynth
No in-app purchases
Retromulator
No in-app purchases







