Comparison

WretchUp vs Krill Synthesizer

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

Head to head
About

WretchUp

This app offers a unique audio manipulation experience, allowing users to create sonic mayhem with pitch-shifted delays, filters, and sampling. It's designed for live performance and studio use, enabling musicians and sound enthusiasts to generate wild noises and unique effects.

Highlights
  • Pitch-shifted delay with feedback and filter
  • Live performance-oriented controls
  • Gesture-based play
  • Record vocals and instruments
  • Sample and manipulate loops
  • Inter-App-Audio and Audiobus support
Features
Read full description

An effect instrument anyone can play - sonic anarchy in the palm of your hand. iOS Mars: "Barely controlled chaos“, "sonic extremes“, "well suited for live use“ Music App Blog: "if you like the occasional dose of sonic mayhem, then this is an app that will let you make it" WretchUp is the sonic instrument from the imagination of Mouse on Mars Instruments. Used by the duo in their live performances, it's a playable effect inspired by analog hardware. Sing into it, speak into it, plug in an instrument, sample sounds, and then make sonic mayhem. It's been tested in Mouse on Mars' live shows and used in studio albums. But now it's available to anyone - whether you're a musician wanting to create unique sounds or you just want to make some wild noises and frighten friends and enemies. // FEATURES - Pitch-shifted delay with feedback and filter - Unique controls, designed to be used in live performance and tested onstage - Play with gestures, even without looking closely at the screen - Record vocals or instruments from the built-in mic or another input - Sample loops and change their speed - Adjust the feedback loop, pitch, and filter for unique sounds - Make inputs by holding down your finger, or lock input for continuous sampling - Inter-App-Audio supported - Audiobus supported www.mouseonmars.com/mominstruments Features artwork by Rupert Smyth. Pure Data-based, open source patch created by Florian Grote and Peter Kirn with Mouse on Mars. App design by Oliver Greschke. Powered by free and open source software libpd. Note: like all mic-based effects, you need to enable microphone input. If you accidentally did not allow mic input, you can allow later via: Device settings, WretchUp, Data settings, Microphone, allow mic input.

About

Krill Synthesizer

This virtual analog polyphonic synthesizer offers a streamlined interface for creating quick synth sounds on iPad. It features two oscillators, an LFO, a low-pass filter, two envelopes, and stereo effects, all accessible from a single screen.

Highlights
  • Virtual analog polyphonic synthesizer
  • Single-screen interface
  • Two oscillators
  • One LFO
  • Low-pass filter
  • Stereo chorus and ping-pong delay
  • 64 presets
Features
Read full description

The GSi Krill Synthesizer was born from a design originally conceived to work as a mono synthesizer on an embedded processor (RP2040), then it was modified to be polyphonic for a more powerful processor (ARM H7) and finally we thought it would be perfect as a AUv3 for iPad, for those quick and dirty synth sounds you sometimes need without getting lost in endless parameter navigation and menu diving. So here it is, just one screen, one knob - one function, what you see is what you get. Two oscillators, one LFO, one low pass filter, two envelopes, stereo chorus, ping-pong delay, 64 presets. Have fun!

Screenshots

WretchUp3 screens
Krill Synthesizer1 screens

Verdict

The call

The clearest difference is rating: Krill Synthesizer at 5.0 against WretchUp's 3.1. Krill Synthesizer also leads on update cadence (weekly vs every 3 weeks) and review sentiment (100% vs 91%). WretchUp's advantage is price ($4.99 vs $11.99). 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

WretchUp costs $4.99 and Krill Synthesizer $11.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Krill Synthesizer holds the better App Store score, 5.0 against 3.1. Both are backed by a comparable volume of ratings — 9 and 6 respectively. Written reviews point the same way: 91% of WretchUp's written reviews are positive against 100% of Krill Synthesizer's.

UpkeepUpdate frequency

WretchUp ships an update every 3 weeks, Krill Synthesizer weekly. The most recent releases landed on October 3, 2026 and October 11, 2026 respectively.

Scorecard4 real differences · 6 level
WretchUp versus Krill Synthesizer: the parameters behind the verdict, then further details
ParameterWretchUpKrill Synthesizer
Price$4.99 — better$11.99
Rating3.1 (9 ratings)5.0 (6 ratings) — better
Positive reviews90.9% of reviews100.0% of reviews — better
Number of ratings9 — better6
Update frequencyEvery 3 weeksWeekly — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS11.011.0
Further details — not scored
Size15 MB8 MB
Age rating4+4+
DeveloperMoMinstruments GbRGenuine Soundware

Customer experience

WretchUp

All ratings9 ratings
Positive55.6%
Neutral0.0%
Negative44.4%
Written reviews11 reviews
Positive90.9%
Neutral0.0%
Negative9.1%

Krill Synthesizer

All ratings6 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews6 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

WretchUp

No in-app purchases

None

Krill Synthesizer

No in-app purchases

Questions

Is WretchUp free?
WretchUp costs $4.99, with no in-app purchases.
Is Krill Synthesizer free?
Krill Synthesizer costs $11.99, with no in-app purchases.
Which has better reviews, WretchUp or Krill Synthesizer?
Krill Synthesizer is rated higher. WretchUp averages 3.1 out of 5 from 9 ratings, while Krill Synthesizer averages 5.0 from 6 ratings.
Do WretchUp or Krill Synthesizer have ads?
Neither WretchUp nor Krill Synthesizer shows ads.
Which is updated more often, WretchUp or Krill Synthesizer?
WretchUp ships an update every 3 weeks, and Krill Synthesizer weekly. Most recently, WretchUp was updated on October 3, 2026 and Krill Synthesizer on October 11, 2026.

Other comparisons