Comparison

Stochastic Signal Processing vs Voltios

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

Head to head
About

Stochastic Signal Processing

Explore the processing of random signals like speech, music, and climate data. This interactive textbook offers dynamic information, films, animations, and 59 real-time laboratory experiments using your device's camera and microphone. It's designed for those with prior signal processing and probability theory knowledge.

Highlights
  • Interactive textbook format
  • Dynamic information display
  • Films and animations
  • 59 laboratory experiments
  • Real-time signal processing
  • Homework problems
Features
Read full description

Speech, music, seismic vibrations, oil prices, and climate measurements are all examples of stochastic (random) signals. In this textbook—intended for individuals with prior training in introductory signal processing and introductory probability theory—we develop techniques to process such signals to extract useful information. We present case studies ranging from music to photographic images to oil prices to climate data to the motion of individual biomolecules. This textbook, as an interactive textbook ("iBook"), makes use of your device's ability to display dynamic information through films and animations and to hear the results of the techniques applied to music. At the end of every chapter there are homework problems ranging from easy to "olympic". We make use of your device's interactive capabilities to offer 59 laboratory experiments in signal processing. The experiments use the camera, the microphone, the speakers, and the graphical user interface. These experiments are not simulations; they are examples of real digital processing of signals in your device. In this time of at-home and online learning, this is the way to learn signal processing through study and experimentation.

About

Voltios

A puzzle game that teaches the fundamentals of electricity through interactive circuit building. Explore various electrical concepts like switches, short circuits, and Ohm's law in a visually engaging and playful manner. Designed for families with no ads or tracking, offering a complete learning experience with a single purchase.

Highlights
  • Interactive circuit building
  • Learn electrical concepts visually
  • Explore switches, fuses, and Ohm's law
  • 68 levels across 9 worlds
  • Offline play
  • No ads or tracking
Features
Currently charting
Read full description

Build circuits, light up the world. Voltios is a puzzle game for learning electricity visually. Connect wires, close switches and watch what changes: a bulb lights up, a motor spins or a fuse protects the circuit. LEARN BY DOING • Discover why current needs a closed circuit. • Experiment with switches, conductors and insulators. • Avoid short circuits and learn how to use fuses. • Compare series and parallel circuits. • Explore Ohm's law and measure voltage and current with the multimeter. 10 WORLDS, 78 LEVELS Keep the original 68 campaign levels and discover 10 new levels in Laboratory, available after completing World 5. All content is included in the app purchase and opens through gameplay progression. First Sparks · Switch It! · Danger: Short Circuit · Measure & Choose · Ohm's Law · Circuit Master · Clocks & Crossings · Real Life · Magnets & Motors · Laboratory. EXPERIMENT AT YOUR OWN PACE • Component explanations, hints and learning recaps. • A daily challenge to keep practising. • A refreshed interface and a multimeter integrated into the board. • English and Spanish. For iPhone and iPad with iOS/iPadOS 17 or later. ONE APP PURCHASE No subscriptions, in-app purchases or ads. No Voltios account required. Gameplay works offline; iCloud, Game Center and sending analytics require a connection. Progress is saved on your device and synced through iCloud when available. Game Center is optional and retains the original campaign achievements. We use TelemetryDeck for interaction analytics with anonymized identifiers, without advertising tracking. See our privacy policy for details.

Screenshots

Stochastic Signal Processing4 screens
Voltios4 screens

Verdict

The call

The clearest difference is price: Stochastic Signal Processing at Free against Voltios's $0.99. Stochastic Signal Processing also leads on in-app purchases (none vs 1) and ratings volume (6 vs 1). Voltios's advantage is rating (5.0 vs 4.7) and update cadence (every 2 weeks vs every 5 weeks). On ads 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

Stochastic Signal Processing is free to download; Voltios costs $0.99 up front. Voltios sells 1 one-off in-app purchase. Stochastic Signal Processing asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

Voltios holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Stochastic Signal Processing has 6 ratings behind it against 1, so its average is the more settled of the two.

UpkeepUpdate frequency

Stochastic Signal Processing ships an update every 5 weeks, Voltios every 2 weeks. The most recent releases landed on October 24, 2026 and October 15, 2026 respectively.

Scorecard8 real differences · 3 level
Stochastic Signal Processing versus Voltios: the parameters behind the verdict, then further details
ParameterStochastic Signal ProcessingVoltios
PriceFree — better$0.99
Rating4.7 (6 ratings)5.0 (1 ratings) — better
Positive reviews66.7% of reviews—
Number of ratings6 — better1
Update frequencyEvery 5 weeksEvery 2 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterPaid
Best chart rank—#196 — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.0 — better17.0
Further details — not scored
Size73 MB6 MB
Age rating4+4+
DeveloperIan YoungIgnacio Noguerol Sicilia

Customer experience

Stochastic Signal Processing

All ratings6 ratings
Positive83.3%
Neutral16.7%
Negative0.0%
Written reviews3 reviews
Positive66.7%
Neutral33.3%
Negative0.0%

Voltios

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Stochastic Signal Processing

No in-app purchases

1 purchases

Voltios

One-time1
  • Full Game$4.99

Questions

Is Stochastic Signal Processing free?
Stochastic Signal Processing is free to download, with no in-app purchases.
Is Voltios free?
Voltios costs $0.99, and also offers in-app purchases.
Which has better reviews, Stochastic Signal Processing or Voltios?
Voltios is rated higher. Stochastic Signal Processing averages 4.7 out of 5 from 6 ratings, while Voltios averages 5.0 from 1 ratings.
Do Stochastic Signal Processing or Voltios have ads?
Neither Stochastic Signal Processing nor Voltios shows ads.
Which is updated more often, Stochastic Signal Processing or Voltios?
Stochastic Signal Processing ships an update every 5 weeks, and Voltios every 2 weeks. Most recently, Stochastic Signal Processing was updated on October 24, 2026 and Voltios on October 15, 2026.

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