Comparison

Fractal Bits vs Hilda Synthesizer

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

Head to head
About

Fractal Bits

Generate an infinite variety of drum sounds using fractal algorithms. Save and share your unique sound sets via text codes. Perform live with multiple keyboard options and record your creations in real-time.

Highlights
  • Infinite unique drum sounds
  • Save/share sound sets via text codes
  • Multiple live drumming keyboards
  • MIDI control and mapping
  • Real-time WAV audio recording
  • Wi-Fi export/import
Features
Read full description

Fractal Bits is a drum synth with over four billion unique sounds created by fractal algorithms. Each set of 12 drums corresponds to a code of 8 characters (you can save/copy/paste it as plain text). Features: * Audio Unit Extension (AUv3), Audiobus; * search for new sounds with three buttons: next random set, edit code, previous set; * three types of keyboards for live drumming: on-screen buttons, PC keyboard, MIDI input; * several processing parameters + control via MIDI; * real-time audio recording to WAV (32-bit); * export to: WAV (one file or a set), SunVox (samples + effects in one file), text clipboard; * the LCK button freezes individual drums - they will not change during the search for new sets; * Wi-Fi export/import. Double clicking on a parameter opens a window for setting the exact value. If you enable the Hold option, the notes will play endlessly, without reacting to key release (noteOff) events; turning the note on again works like turning it off; there are two ways to enable this option: 1) using the Hold parameter in the "MIDI Mapping" window; 2) by pressing the HOLD button, which appears in place of LCK while playing the musical keyboard: press HOLD, release the desired notes - then the released notes will continue to play.

About

Hilda Synthesizer

This app offers a complex oscillator monosynth with a blend of west-coast and east-coast synthesis techniques. It features a wave folder, lowpass gate, 12-mode filter, and VCA circuit, all meticulously circuit-modelled for authentic analog or digital sound. It functions as a playable synth, MIDI sequencer, and audio effect.

Highlights
  • Complex Oscillator Monosynth
  • Wave folder and lowpass gate
  • 12-mode filter
  • Circuit-modelled analog sound
  • Built-in 16-step MIDI Sequencer
  • Audio effect for external audio
  • AUv3 compatibility
Features
Read full description

Hilda is a Complex Oscillator Monosynth, inspired by the most interesting aspects of both west-coast and east-coast synthesis techniques. You'll find a wave folder, lowpass gate, and audio-rate modulations, but also a 12-mode filter and traditional VCA circuit. All parts of the instrument are carefully circuit-modelled to sound as analog (or digital, where applicable) as possible. It's like a best-of-all-worlds semi modular synth, but without the patch cables. The unique mix of different synthesis components adds up to a unique sounding electronic instrument, which can be used as a playable synthesizer, a MIDI sequencer and an audio effect for external audio - or any combination of those three. - Full Audio Unit compatibility (AUv3 instrument, audio effect and MIDI processor modes supported) - Universal design (iPhone and iPad; iPad Air 2 or higher recommended) - Built-in analog style 16 Step MIDI Sequencer with custom scales - 12 mode filter, based on the Oberheim Xpander design - Drone mode lets you [partially] bypass the VCA/LPG and just go with the flow - DIY Lo-Fi digital delay circuit emulation - Live pads with effects that can be triggered via the UI (or via exposed AU Parameters) - All synth settings exposed a AU Parameters (for automation and MIDI learning in your host of choice) - MIDI Processor plugin mode disables synth to save CPU - Carefully handcrafted by yours truly, to capture the essence of my love for tinkering and experimenting with sound :-) Find the user manual on ruismaker.com

Screenshots

Fractal Bits2 screens
Hilda Synthesizer3 screens

Verdict

The call

The clearest difference is price: Fractal Bits at $1.99 against Hilda Synthesizer's $12.99. Hilda Synthesizer's advantage is update cadence (every 9 days vs every 5 months). On rating, review sentiment, ratings volume and ads 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

Fractal Bits costs $1.99 and Hilda Synthesizer $12.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.9 for Fractal Bits against 4.9 for Hilda Synthesizer. Both are backed by a comparable volume of ratings — 82 and 58 respectively. Written reviews split almost evenly too, at 91% and 90% positive.

UpkeepUpdate frequency

Fractal Bits ships an update every 5 months, Hilda Synthesizer every 9 days. The most recent releases landed on November 3, 2026 and November 2, 2026 respectively.

Scorecard2 real differences · 8 level
Fractal Bits versus Hilda Synthesizer: the parameters behind the verdict, then further details
ParameterFractal BitsHilda Synthesizer
Price$1.99 — better$12.99
Rating4.9 (82 ratings)4.9 (58 ratings) — better
Positive reviews90.7% of reviews — better90.0% of reviews
Number of ratings82 — better58
Update frequencyEvery 5 monthsEvery 9 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS12.012
Further details — not scored
Size7 MB6 MB
Age rating4+4+
DeveloperAlexander ZolotovBram Bos

Customer experience

Fractal Bits

All ratings80 ratings
Positive96.3%
Neutral0.0%
Negative3.8%
Written reviews43 reviews
Positive90.7%
Neutral7.0%
Negative2.3%

Hilda Synthesizer

All ratings58 ratings
Positive98.3%
Neutral0.0%
Negative1.7%
Written reviews30 reviews
Positive90.0%
Neutral0.0%
Negative10.0%

In-app purchases

None

Fractal Bits

No in-app purchases

None

Hilda Synthesizer

No in-app purchases

Questions

Is Fractal Bits free?
Fractal Bits costs $1.99, with no in-app purchases.
Is Hilda Synthesizer free?
Hilda Synthesizer costs $12.99, with no in-app purchases.
Which has better reviews, Fractal Bits or Hilda Synthesizer?
Hilda Synthesizer is rated higher. Fractal Bits averages 4.9 out of 5 from 82 ratings, while Hilda Synthesizer averages 4.9 from 58 ratings.
Do Fractal Bits or Hilda Synthesizer have ads?
Neither Fractal Bits nor Hilda Synthesizer shows ads.
Which is updated more often, Fractal Bits or Hilda Synthesizer?
Fractal Bits ships an update every 5 months, and Hilda Synthesizer every 9 days. Most recently, Fractal Bits was updated on November 3, 2026 and Hilda Synthesizer on November 2, 2026.

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