Comparison

ThetaCalc vs SwiftRPN

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

Head to head
About

ThetaCalc

This utility app provides a Reverse Polish Notation (RPN) calculator. Users can extend its functionality by programming custom functions and equations using JavaScript.

Highlights
  • Reverse Polish Notation (RPN) calculator
  • User-programmable functions
  • JavaScript equation support
  • Extensible functionality
Features
Read full description

ThetaCalc is a RPN (Reverse Polish Notation) calculator which can be extended by functions and equations programmed by the user in JavaScript.

About

SwiftRPN

This utility app provides a powerful Reverse Polish Notation (RPN) calculator with advanced features. It supports scalar types, vectors, and matrices, along with extensive built-in operators and unit conversions. Easily switch between number bases and visualize results.

Highlights
  • RPN stack for efficient calculations
  • Support for scalar, vector, and matrix types
  • 84 built-in operators with documentation
  • 74 built-in units for conversion
  • Multiple number base input and output (binary, octal, decimal, hex)
  • BigInt support for integer calculations
Read full description

SwiftRPN is an RPN (Reverse Polish Notation) calculator that aims to be quick to open and easy to use. = RPN Stack Work quickly and efficiently using the RPN Stack by pushing and popping values. The stack will always show what series of inputs led to each output, so you won't lose context during complicated expressions. = Extended Types SwiftRPN can understand scalar types like integers and real numbers, as well as vectors and square matrices of sizes 2, 3, and 4. When operating purely in the scalar integer domain, SwiftRPN can promote up to BigInts to avoid floating point imprecision. = Operators SwiftRPN has 84 built-in operators with included documentation and examples. All the expected operators (basic arithmetic, exponents, logarithms) are present, as are: - Rounding functions (floor/ceil/trunc/round) - Unit conversions - Bitwise operations (and/or/not/xor/shift left/shift right) - Statistics (avg/min/max/sum/std dev/NPV) - Trigonometry (sin/cos/tan + arc/hyperbolic variants) - Vector operations (dot/cross/normalize/length/swizzle) - Matrix operations (identity/inverse/transpose + translation/scale/rotation matrix generators) = Unit Conversions SwiftRPN has 74 built-in units, and can convert between units within families, including: - Angle - Area - Colors (3 and 4 components) - Coordinate systems (2D and 3D) - Length - Mass - Storage (Base 10 [SI, 1000 bytes in a kb] and Base 2 [1024 bytes in a kb]) - Temperature - Time - Volume = Value Representation SwiftRPN recognizes values represented in binary, octal, decimal, and hexidecimal. You can: - Enter values in one representation, and convert them to another - See the result of bitwise operations in binary automatically - View vec3 and vec4 components (truncated) in hexidecimal when working with colors.

Screenshots

ThetaCalc4 screens
SwiftRPN4 screens

Verdict

The call

The clearest difference is rating: SwiftRPN at 5.0 against ThetaCalc's 4.3. ThetaCalc's advantage is update cadence (every 3 months vs every 14 months) and ratings volume (4 vs 1). 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. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

SwiftRPN holds the better App Store score, 5.0 against 4.3. Both are backed by a comparable volume of ratings — 4 and 1 respectively.

UpkeepUpdate frequency

ThetaCalc ships an update every 3 months, SwiftRPN every 14 months. Both last shipped on November 3, 2026.

Scorecard3 real differences · 7 level
ThetaCalc versus SwiftRPN: the parameters behind the verdict, then further details
ParameterThetaCalcSwiftRPN
PriceFreeFree
Rating4.3 (4 ratings)5.0 (1 ratings) — better
Positive reviews100.0% of reviews—
Number of ratings4 — better1
Update frequencyEvery 3 months — betterEvery 14 months
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.617.6
Further details — not scored
Size1 MB3 MB
Age rating4+4+
DeveloperFelix StehliPatrick Gelvin

Customer experience

ThetaCalc

All ratings4 ratings
Positive75.0%
Neutral25.0%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

SwiftRPN

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

In-app purchases

None

ThetaCalc

No in-app purchases

None

SwiftRPN

No in-app purchases

Questions

Is ThetaCalc free?
ThetaCalc is free to download, with no in-app purchases.
Is SwiftRPN free?
SwiftRPN is free to download, with no in-app purchases.
Which has better reviews, ThetaCalc or SwiftRPN?
SwiftRPN is rated higher. ThetaCalc averages 4.3 out of 5 from 4 ratings, while SwiftRPN averages 5.0 from 1 ratings.
Do ThetaCalc or SwiftRPN have ads?
Neither ThetaCalc nor SwiftRPN shows ads.
Which is updated more often, ThetaCalc or SwiftRPN?
ThetaCalc ships an update every 3 months, and SwiftRPN every 14 months. Most recently, ThetaCalc was updated on November 3, 2026 and SwiftRPN on November 3, 2026.

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