FT8 Decoder vs Modern RPN
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
FT8 Decoder
This application decodes FT8 digital signals from amateur radio bands. It can process audio from external sources or directly from an SSB radio or SDR. The app also generates FT8 modulated audio for experimentation.
- Decodes FT8 8FSK modulated signals
- Processes external audio or SDR sound
- Supports standard callsigns and 13-character messages
- Generates FT8 message audio
- Experiment with sending and receiving FT8 audio
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An FT8 decoder. FT8 is a weak signal digital mode, currently very popular in the amateur radio HF shortwave bands. The ft8d app allows decoding FT8 8FSK modulated signals contained in externally provided audio or sound from an SSB radio or SDR. The app supports Level 1 decoding of messages with standard callsigns or 13 character free text messages. The app can also generate standard FT8 message audio, so can be used to experiment with sending and receiving FT8 encoded and modulated audio. The app does NOT perform Auto-sequencing, or decode long hashed callsigns.
Modern RPN
A minimalist reverse Polish notation calculator for iOS devices. It offers Standard, Binary, and Hex modes for quick calculations and programmer-friendly conversions, featuring a clean interface and a 4-level stack.
- Reverse Polish Notation (RPN) input
- Standard, Binary, and Hex modes
- 4-level visible stack
- Calculation history
- Saved session state
- Clean dark interface
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Modern RPN is a minimalist reverse polish notation calculator for iPhone and iPad, with Standard, Binary, and Hex modes for fast everyday math and programmer-friendly conversions. Use a clean 4-level stack, instant mode switching, calculation history, and saved session state to move quickly without clutter. Features: • True RPN input with ENTER to push or duplicate values • Standard, Binary, Financial, and Hex calculator modes • Mode-aware entry and display formatting • 4-level visible stack: T, Z, Y, X • Core operations: add, subtract, multiply, divide • Stack tools: POP, X/Y swap, sign toggle, backspace, and all clear • Calculation history with timestamps • History filtering by All, Standard, Binary, Financial, or Hex • Saved session state for your current mode, stack, and in-progress input • Clean dark interface designed for focus and readability • No accounts, no ads, no data collection Modern RPN is designed for people who want the speed of a classic RPN calculator with a modern iOS interface.
Screenshots
Verdict
The clearest difference is review sentiment: Modern RPN at 100% against FT8 Decoder's 50%. Modern RPN also leads on rating (5.0 vs 4.3) and update cadence (every 5 days vs every 18 months). FT8 Decoder's advantage is ratings volume (8 vs 1) and price ($1.99 vs $2.99). 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
FT8 Decoder costs $1.99 and Modern RPN $2.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Modern RPN holds the better App Store score, 5.0 against 4.3. That said, the two scores are not equally well evidenced: FT8 Decoder has 8 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 50% of FT8 Decoder's written reviews are positive against 100% of Modern RPN's.
FT8 Decoder ships an update every 18 months, Modern RPN every 5 days. The most recent releases landed on October 8, 2026 and October 7, 2026 respectively.
| Parameter | FT8 Decoder | Modern RPN |
|---|---|---|
| Price | $1.99 — better | $2.99 |
| Rating | 4.3 (8 ratings) | 5.0 (1 ratings) — better |
| Positive reviews | 50.0% of reviews | 100.0% of reviews — better |
| Number of ratings | 8 — better | 1 |
| Update frequency | Every 18 months | Every 5 days — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Paid | Paid |
| Devices | iPhone, iPod | iPhone, iPad |
| Requires iOS | 15.4 — better | 26.2 |
| Further details — not scored | ||
| Size | 1 MB | 2 MB |
| Age rating | 4+ | 4+ |
| Developer | HotPaw Productions | Kevin Flathers |
Customer experience
FT8 Decoder
Modern RPN
In-app purchases
FT8 Decoder
No in-app purchases
Modern RPN
No in-app purchases
