Comparison

MIDI Opener vs Granula Synth

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

Head to head
About

MIDI Opener

This app is a powerful and modern MIDI player designed for musicians, learners, and creators. It offers visual playback, tempo and key control, and advanced track management. Import custom soundbanks and enjoy features like synchronized lyrics and a 3D visualizer.

Highlights
  • Visual MIDI playback
  • Tempo and key control
  • Advanced track controls
  • 128 General MIDI instruments
  • Built-in effects
  • Custom soundbanks
  • Synchronized lyrics
  • 3D visualizer
Features
Read full description

MIDI Opener – Play, Practice & Export MIDI Files Open any MIDI file and take full control of your music. MIDI Opener is a fast, precise MIDI player built for musicians who want to practice smarter, isolate parts, customize arrangements, route playback to external gear, export their changes, and deeply explore songs without the complexity of a DAW. WHY MIDI OPENER • Instantly open and play standard MIDI files (.mid, .midi) • Ultra-responsive playback with zero clutter • Built for practice, learning, live performance, and musical exploration • Completely ad-free POWERFUL PLAYBACK CONTROL • Change tempo in real time (slow down or speed up) • Transpose key instantly to match your instrument • Mute, solo, and adjust volume for each track • Swap instruments using all 128 General MIDI sounds • Import custom SoundFont (.sf2) and DLS soundbanks • Apply reverb, delay, distortion, and EQ effects EXPORT YOUR CHANGES • Export audio as MP3, M4A, or WAV • Export modified MIDI files with your changes • Save customized practice mixes and arrangements • Perfect for backing tracks, sharing, and rehearsal prep PRACTICE WITH PRECISION • Loop any section with A–B looping • Isolate difficult passages and repeat them • Break down complex songs into manageable parts • Save and instantly restore full practice setups with Snapshots Perfect for pianists, guitarists, producers, singers, music directors, and students. MIDI OUT & EXTERNAL DEVICES • Send MIDI playback to external keyboards, synths, drum machines, and sound modules • Connect over USB, Bluetooth, or Wi-Fi • Compatible with Logic Pro, Ableton Live, GarageBand, and CoreMIDI apps • Use premium external instrument sounds and studio hardware SING AND PRACTICE • View embedded lyrics when available • Real-time word highlighting synced to playback • Great for karaoke and vocal practice SEE YOUR MUSIC • Clean, readable note timeline • Beautiful full screen Focus Mode with ambient visuals, auto hiding controls, and optional synchronized lyrics • Track based visual layout • Retro 3D visualizer • Multiple visual themes ORGANIZE YOUR MIDI LIBRARY • Import from Files, AirDrop, Mail, and other apps • Create playlists • Queue songs for continuous playback UPGRADE OPTIONS Free — The Player & Customizer Open and play MIDI files with powerful built-in customization tools. Includes instrument swapping with all 128 General MIDI sounds, custom SoundFont and DLS support, synchronized lyrics, audio effects, song section looping, visual themes, saved mixes with Snapshots, playlists, queue support, and a complete MIDI song library experience—all in a fast, focused, ad-free player. Practice Pack — The Musician’s Upgrade Unlock advanced practice and arrangement tools including real-time tempo control, key transposition, per-track mute, solo, and volume controls, plus MP3 audio and MIDI export for creating custom practice mixes, backing tracks, and arrangements. MIDI Out — The Producer’s Upgrade Route MIDI playback to external keyboards, synths, drum machines, DAWs, and professional music hardware over USB, Bluetooth, or Wi-Fi using CoreMIDI. All Access — Everything, Once Get the complete MIDI Opener experience with every upgrade included, plus discounted upgrade pricing if you already own another product. FAST. FOCUSED. NO DISTRACTIONS. Made for musicians who want control—not complexity.

About

Granula Synth

Explore new soundscapes by manipulating granular audio. This app offers a library of presets, custom sound import, and extensive parameter adjustments for unique music creation. Save your settings and share your sonic experiments.

Highlights
  • Granular sound manipulation
  • Preset library
  • Custom sound import
  • Parameter adjustment
  • Save user settings
  • Share audio recordings
Features
Read full description

Push the boundaries of sound design. Granula Synth turns granular synthesis into a playground — grab tiny grains of audio, scatter them across the waveform, and shape them into pads, textures, and soundscapes no other synth can make. What's inside: - Curated preset library, crafted by sound designers - Deep grain controls — length, position, direction, pitch, and more - Powerful modulation matrix with dual LFOs and chaos generators - Built-in envelope, EQ, and FX chain - Import your own audio or record directly in the app - Save, organize, and share your presets - Export your ideas straight to your DAW Whether you're scoring film, building ambient textures, or just exploring new sonic territory, Granula Synth gives you granular control over every grain of sound. Privacy Policy: https://sites.google.com/view/castles-trip-privacy-policy Terms of Use: https://sites.google.com/view/granula-tos

Screenshots

MIDI Opener4 screens
Granula Synth4 screens

Verdict

The call

The clearest difference is review sentiment: MIDI Opener at 64% against Granula Synth's 20%. MIDI Opener also leads on rating (3.9 vs 1.8) and update cadence (every 6 days vs every 25 months). Granula Synth's advantage is iOS requirement (12.0 vs 17.6). On price, 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

Both are free to download. MIDI Opener sells 13 one-off in-app purchases and Granula Synth sells 3 in-app purchases, starting at $2.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

MIDI Opener holds the better App Store score, 3.9 against 1.8. That said, the two scores are not equally well evidenced: MIDI Opener has 86 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 64% of MIDI Opener's written reviews are positive against 20% of Granula Synth's.

UpkeepUpdate frequency

MIDI Opener ships an update every 6 days, Granula Synth every 25 months. The most recent releases landed on October 22, 2026 and October 18, 2026 respectively.

Scorecard5 real differences · 5 level
MIDI Opener versus Granula Synth: the parameters behind the verdict, then further details
ParameterMIDI OpenerGranula Synth
PriceFreeFree
Rating3.9 (86 ratings) — better1.8 (4 ratings)
Positive reviews64.5% of reviews — better20.0% of reviews
Number of ratings86 — better4
Update frequencyEvery 6 days — betterEvery 25 months
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFreemium
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS17.612.0 — better
Further details — not scored
Size334 MB75 MB
Age rating4+4+
DeveloperMartianRoverStanislav Duplinskiy

Customer experience

MIDI Opener

All ratings86 ratings
Positive72.1%
Neutral8.1%
Negative19.8%
Written reviews76 reviews
Positive64.5%
Neutral11.8%
Negative23.7%

Granula Synth

All ratings4 ratings
Positive25.0%
Neutral0.0%
Negative75.0%
Written reviews5 reviews
Positive20.0%
Neutral20.0%
Negative60.0%

Bugs and requests

MIDI Opener

Reported bugs

15 issues
  • Sustained notes are treated as staccato notes.
  • Cuts off the beginning of the song.
  • Kicked out of the app when clicking on another SoundFont.
  • Crashes when changing SoundFonts (iOS 26).
  • Bass drum is too quiet for metal music.
Show 10 more
  • Changing key option breaks songs.
  • App crashes on startup.
  • Randomly playing a single track only.
  • Skipping individual notes when too many are playing.
  • New update not working, won't play audio or understand certain instruments.
  • Google Drive method does not work.
  • Download button does nothing.
  • Skips a lot of notes.
  • No sound, plays silence.
  • Scrolling bar with no sound.

Requested features

18 requests
  • Adjust individual track volumes
  • Zoom in/out
  • Select region to play
  • Export features (WAV, MP3, FLAC)
  • Playlist functionality
Show 13 more
  • Library structure with nested folders
  • AUV3 plug-in support
  • IAA with audio hosts
  • Switchable color schemes
  • Spectrum editor/video export
  • Save MIDI soundfiles as MP3
  • More SoundBanks
  • Tempo control
  • Transpose option
  • Custom SoundFont support
  • Local storage/in-app folder
  • Background play
  • Option to play once (no loop)

Granula Synth

Not enough reviews yet to summarise bugs or requests.

In-app purchases

13 purchases

MIDI Opener

One-time13
  • Tip$0.99
  • Full Upgrade Discount$0.99
  • Remove Ads$1.99
Show 10 more
  • Change Tempo$1.99
  • Change Tempo and Key$1.99
  • All Access Upgrade$2.99
  • Track Controls$2.99
  • Super Tip$4.99
  • MIDI Out$4.99
  • Practice Pack$4.99
  • Full Upgrade$4.99
  • Premium Upgrade$4.99
  • All Access$7.99
3 purchases

Granula Synth

Subscriptions3
  • Access to app features3 Days trial$2.991 Month
  • Access to app features3 Days trial$7.493 Months
  • Access to app features3 Days trial$8.996 Months

Questions

Is MIDI Opener free?
MIDI Opener is free to download, with in-app purchases available.
Is Granula Synth free?
Granula Synth is free to download, with in-app purchases available.
Which has better reviews, MIDI Opener or Granula Synth?
MIDI Opener is rated higher. MIDI Opener averages 3.9 out of 5 from 86 ratings, while Granula Synth averages 1.8 from 4 ratings.
Do MIDI Opener or Granula Synth have ads?
Neither MIDI Opener nor Granula Synth shows ads.
Which is updated more often, MIDI Opener or Granula Synth?
MIDI Opener ships an update every 6 days, and Granula Synth every 25 months. Most recently, MIDI Opener was updated on October 22, 2026 and Granula Synth on October 18, 2026.

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