Comparison

MIDIWriter vs spectwhirl

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

Head to head
About

MIDIWriter

This app transforms keyboard input into musical notes and sounds. Type characters to instantly generate MIDI messages, or input phrases to create musical sequences with adjustable tempo and looping. It includes a built-in sound engine and supports external MIDI devices and apps.

Highlights
  • Text to MIDI conversion
  • Built-in General MIDI sound engine
  • Phrase playback with tempo control
  • Drum mode with multiple kits
  • External MIDI output
  • Hardware keyboard support
  • Wi-Fi MIDI networking
Features
Read full description

[[ A STRANGE MUSIC TOOL FOR MANIAC MUSIC LOVERS! ]] MIDIWriter is a unique app that converts keyboard input into MIDI note messages. Each character you type instantly produces sound. You can also enter a phrase and play it back as a sequence with adjustable tempo and loop options. KEY FEATURES: Built-in Sound Engine: No external app required! MIDIWriter includes a built-in General MIDI sound engine with 128 instruments and 9 drum kits. Just type and hear the sound immediately. Phrase Playback: Enter any text and play it as a musical sequence. Adjust the tempo (1-480 BPM), enable loop mode, and let your words become music. Space characters can be used as rests. Drum Mode: Switch to drum mode to play percussion sounds. Choose from 9 GM drum kits including Standard, Room, Power, Electronic, 808/909, Jazz, Brush, and Orchestral. MIDI Output: Send MIDI to other apps or external devices. Configure MIDI channel (1-16), program change (0-127), and destination. Works with Virtual MIDI and MIDI Network Session. Can be used simultaneously with the built-in sound engine. Keyboard Support: Use the on-screen software keyboard, or connect a Bluetooth/USB hardware keyboard for a real typing experience. Supports Japanese input with proper IME handling. MIDI Network Session: Connect to Mac or other iOS devices over Wi-Fi to control CoreMIDI-compatible sound generators remotely. Dark Mode & Rotation: Full support for light and dark modes. Works in portrait and landscape orientations on both iPhone and iPad. Note: Playback stops when the app goes to background. Using the Built-in Sound: Simply launch MIDIWriter and start typing. Each key produces a unique sound based on its character code. Enable drum mode in Settings for percussion sounds. Using with External MIDI Apps (Virtual MIDI): 1. Open a CoreMIDI sound generator app. 2. In MIDIWriter Settings, turn on "MIDI Output" and select the destination. 3. Type any key to hear sound from the external app. Using with Mac (MIDI Network Session): 1. Connect iPhone and Mac to the same Wi-Fi network. 2. Open MIDIWriter on iPhone. 3. On Mac, open "Audio MIDI Setup" and configure Network MIDI. 4. Connect your iPhone to the session. 5. Open a CoreMIDI app on Mac and select the network session as MIDI input. 6. Type on MIDIWriter to play sounds on Mac. Credits: Built-in sound engine uses "GeneralUser GS" SoundFont by S. Christian Collins. https://schristiancollins.com/generaluser.php

About

spectwhirl

This audio effect app transforms input sound into new textures and bell-like tones by extracting and manipulating sinewave components. It offers advanced control over delay lines, frequency shifting, and filtering, with gesture recording for parameter automation.

Highlights
  • Sinewave component extraction and grouping
  • Delay lines with feedback
  • Frequency shifter and sample-and-hold effects
  • Configurable filtering
  • Gesture recording for automation
  • Scene saving and management
Features
Read full description

"bells and whistles, literally" spectwhirl is a hybrid spectral audio effect. It can extract and rearrange sinewave components from input signal to make new sound textures and bell-like sounds. * input sound is converted to sinewave components that are divided into 4 groups: harmonic, inharmonic, 12-edo and other * each component is fed into a delay line with feedback * there is a group of frequency shifter and sample-and-hold effects before and after delay lines * each set of sinewave components can be filtered * all the parameters can be instantly automated with gesture recording !!! Please note that this effect consumes much CPU and requires a modern device. ====================== Quick Start: Top row of controls enables different parts of user interface: scenes editor ("scene"), controls switch ("edit") and "zoom" controls When "edit" is switch on, you can show or hide various controls (marked as "ctrl") and switch gesture recording automation for some of them (marked with ">") Main control surface displays sonogram with tracked elements. Colors are set accordingly to the group they are assigned (red-orange-green-blue are for harmonic, inharmonic, 12-edo and others). Each "lane" contains delay time controls. * Triangle facing left is for the start locator, it determines initial delay time * Square moves both start and end locators together * When left locator is first moved you can see the right locator with the same triangle. It shows the end of the selected region, the secondary delay time is determined by the difference between left and right locators * if you drag over the area of the region in a lane, the four-dotted/one circle indicator will change its appearance; this changes the arpeggio mode of the region. If set to leftmost position (one circle) the components go in-sync; if set to maximum value (shown as diagonal line with circles) - components are played sequentially * all settings can be stored as "scene" and multiple scenes can be switched sequentially; there is a set of button to move, add and delete scenes. All scenes will be stored as machine state; it can be exported / imported as a single file or as separate file with current scene in the "setup" view The standalone version always starts with output level set to -70 dB to avoid feedback

Screenshots

MIDIWriter4 screens
spectwhirl4 screens

Verdict

The call

The clearest difference is rating: spectwhirl at 4.0 against MIDIWriter's 1.5. spectwhirl also leads on review sentiment (33% vs 0%) and update cadence (every 5 weeks vs every 35 months). MIDIWriter's advantage is price ($0.99 vs $4.99). On ratings volume, ads, in-app purchases and monetization model 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

MIDIWriter costs $0.99 and spectwhirl $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

spectwhirl holds the better App Store score, 4.0 against 1.5. Both are backed by a comparable volume of ratings — 2 and 5 respectively. Written reviews point the same way: 0% of MIDIWriter's written reviews are positive against 33% of spectwhirl's.

UpkeepUpdate frequency

MIDIWriter ships an update every 35 months, spectwhirl every 5 weeks. The most recent releases landed on November 1, 2026 and November 3, 2026 respectively.

Scorecard5 real differences · 5 level
MIDIWriter versus spectwhirl: the parameters behind the verdict, then further details
ParameterMIDIWriterspectwhirl
Price$0.99 — better$4.99
Rating1.5 (2 ratings)4.0 (5 ratings) — better
Positive reviews0.0% of reviews33.3% of reviews — better
Number of ratings25 — better
Update frequencyEvery 35 monthsEvery 5 weeks — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS16.012.0 — better
Further details — not scored
Size31 MB7 MB
Age rating4+4+
DeveloperMasayuki AkamatsuAlexey Nadzharov

Customer experience

MIDIWriter

All ratings2 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews4 reviews
Positive0.0%
Neutral0.0%
Negative100.0%

spectwhirl

All ratings5 ratings
Positive60.0%
Neutral20.0%
Negative20.0%
Written reviews3 reviews
Positive33.3%
Neutral33.3%
Negative33.3%

In-app purchases

None

MIDIWriter

No in-app purchases

None

spectwhirl

No in-app purchases

Questions

Is MIDIWriter free?
MIDIWriter costs $0.99, with no in-app purchases.
Is spectwhirl free?
spectwhirl costs $4.99, with no in-app purchases.
Which has better reviews, MIDIWriter or spectwhirl?
spectwhirl is rated higher. MIDIWriter averages 1.5 out of 5 from 2 ratings, while spectwhirl averages 4.0 from 5 ratings.
Do MIDIWriter or spectwhirl have ads?
Neither MIDIWriter nor spectwhirl shows ads.
Which is updated more often, MIDIWriter or spectwhirl?
MIDIWriter ships an update every 35 months, and spectwhirl every 5 weeks. Most recently, MIDIWriter was updated on November 1, 2026 and spectwhirl on November 3, 2026.

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