ThetaCalc vs SmartPLL
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
ThetaCalc
This utility app provides a Reverse Polish Notation (RPN) calculator. Users can extend its functionality by programming custom functions and equations using JavaScript.
- Reverse Polish Notation (RPN) calculator
- User-programmable functions
- JavaScript equation support
- Extensible functionality
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ThetaCalc is a RPN (Reverse Polish Notation) calculator which can be extended by functions and equations programmed by the user in JavaScript.
SmartPLL
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The Z-COMM SSG series of Smart Phase Locked Loop (PLL) modules provide high performance in a compact package suitable for any number of applications. Fully programmable through a unique Bluetooth interface, or USB cable, the user may adjust functions such as frequency, sweep mode, step time, step size, and power output, among others. LED indicators provide a visual cue of the status of the various functions. Its rugged enclosure lends itself to in-field use as well as bench top testing. The highly reliable output signal, excellent phase noise, and flexibility of an internal reference or input for an external reference, provides RF engineers with an adaptable RF tool.
Screenshots
Verdict
The clearest difference is update cadence: ThetaCalc at every 3 months against SmartPLL's every 19 months. SmartPLL's advantage is iOS requirement (13.1 vs 17.6). On price, ads, in-app purchases 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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
ThetaCalc ships an update every 3 months, SmartPLL every 19 months. The most recent releases landed on June 1, 2026 and September 18, 2026 respectively.
| Parameter | ThetaCalc | SmartPLL |
|---|---|---|
| Price | Free | Free |
| Rating | 4.3 (4 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 4 — better | — |
| Update frequency | Every 3 months — better | Every 19 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 17.6 | 13.1 — better |
| Further details — not scored | ||
| Size | 1 MB | 1 MB |
| Age rating | 4+ | 4+ |
| Developer | Felix Stehli | Z-Communications |
In-app purchases
ThetaCalc
No in-app purchases
SmartPLL
No in-app purchases









