Comparison

Uber Synth vs Stellr

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

Head to head
About

Uber Synth

This app offers a polyphonic multi-timbral FM synthesizer for iOS devices. It features a triple-oscillator sound engine with five distinct multi-timbral options for creating evolving and complex soundscapes. Supports Audiobus for integration with other music apps.

Highlights
  • Polyphonic multi-timbral FM synthesizer
  • Triple-oscillator cross-modulated FM engine
  • Five multi-timbral options
  • Sound map and sound palettes
  • Evolving sound generation
  • Audiobus support
Features
Read full description

Uber Synth is a polyphonic multi-timbral frequency modulated (FM) synthesizer that runs on any iOS device. The underlying sound engine is based on the triple-oscillator cross-modulated FM synthesizer first introduced in our xMod app. Uber Synth provides five multi-timbral options: 1) Mix the sounds of any two sound patches, 2) combine patches using the sound map, 3) Generate specified as well as randomized sound palettes across the keyboard, 4) Specify a region in sound space centered on a sound and move a point by a variable randomized amount within the region each time you play a note to create an evolving mix of the center sound and the sound nearest the point. 5) Do the same as above moving the point automatically at a specified rate. Supports Audiobus.

About

Stellr

Create deep, ethereal ambiance with a pitch-shifter, dual delays, and reverb. Explore sonic possibilities with 15 presets, randomization, and parameter automation. Enhance your music with a new dimension of sound.

Highlights
  • Pitch shifter with fine-tuning or semitone snap
  • Two independent delays for complex feedback
  • LFO modulation and various reverb types
  • Pre-gain and dry/wet level control
  • Audio Unit Extension, Audiobus, Inter-App Audio support
  • 15 built-in presets with import/export
  • Realtime frequency spectrum visualizer
Features
Read full description

Stellr is a pitch-shifter/delay/reverb sound processor aimed to recreate the classic shimmer effect. It makes deep ethereal ambiance on top of your sound, providing you with a wide variety of sonic possibilities. Add a new dimension to your music. The effect features 20 ready to use presets which can be shared between devices as well as randomize button for endless variations. When loaded as Audio Unit effect, all parameters can be automated via host app. Stellr main features: – Pitch shifter which can be fine-tuned or snapped to semitone – Two separate delays for creating a complex feedback effect – LFO modulation and different types of reverb – Set pre-gain and dry/wet levels – Audio Unit Extension support – 20 built-in presets – Low-pass and High-pass filters – Ability to save and randomize parameters – Import and export of user presets – Realtime frequency spectrum visualizer

Screenshots

Uber Synth4 screens
Stellr2 screens

Verdict

The call

The clearest difference is rating: Stellr at 3.4 against Uber Synth's 2.0. Stellr also leads on review sentiment (67% vs 50%) and ratings volume (9 vs 1). Uber Synth's advantage is update cadence (every 3 months vs every 40 months) and price ($3.99 vs $4.99). On ads, in-app purchases, monetization model and device support 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

Uber Synth costs $3.99 and Stellr $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Stellr holds the better App Store score, 3.4 against 2.0. That said, the two scores are not equally well evidenced: Stellr has 9 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 50% of Uber Synth's written reviews are positive against 67% of Stellr's.

UpkeepUpdate frequency

Uber Synth ships an update every 3 months, Stellr every 40 months. The most recent releases landed on September 29, 2026 and October 2, 2026 respectively.

Scorecard6 real differences · 4 level
Uber Synth versus Stellr: the parameters behind the verdict, then further details
ParameterUber SynthStellr
Price$3.99 — better$4.99
Rating2.0 (1 ratings)3.4 (9 ratings) — better
Positive reviews50.0% of reviews66.7% of reviews — better
Number of ratings19 — better
Update frequencyEvery 3 months — betterEvery 40 months
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS14.012.0 — better
Further details — not scored
Size7 MB26 MB
Age rating4+4+
DeveloperMark CarlottoBACKPULLVER SOFTWARE LTD OOD

Customer experience

Uber Synth

All ratings1 ratings
Positive0.0%
Neutral0.0%
Negative100.0%
Written reviews8 reviews
Positive50.0%
Neutral12.5%
Negative37.5%

Stellr

All ratings9 ratings
Positive55.6%
Neutral11.1%
Negative33.3%
Written reviews3 reviews
Positive66.7%
Neutral0.0%
Negative33.3%

In-app purchases

None

Uber Synth

No in-app purchases

None

Stellr

No in-app purchases

Questions

Is Uber Synth free?
Uber Synth costs $3.99, with no in-app purchases.
Is Stellr free?
Stellr costs $4.99, with no in-app purchases.
Which has better reviews, Uber Synth or Stellr?
Stellr is rated higher. Uber Synth averages 2.0 out of 5 from 1 ratings, while Stellr averages 3.4 from 9 ratings.
Do Uber Synth or Stellr have ads?
Neither Uber Synth nor Stellr shows ads.
Which is updated more often, Uber Synth or Stellr?
Uber Synth ships an update every 3 months, and Stellr every 40 months. Most recently, Uber Synth was updated on September 29, 2026 and Stellr on October 2, 2026.

Other comparisons