# Feld Hellschreiber vs SDR

The clearest difference is price: Feld Hellschreiber at $2.99 against SDR's $49.99. Feld Hellschreiber also leads on device support (3 vs 1) and iOS requirement (6.0 vs 17.6). SDR's advantage is rating (4.2 vs 2.8) and update cadence (every 2 weeks vs every 13 months). On review sentiment, ads, in-app purchases and monetization model there is nothing between them.

Feld Hellschreiber costs $2.99 and SDR $49.99 up front. Neither carries in-app purchases, so what you see is what you pay.

SDR holds the better App Store score, 4.2 against 2.8. That said, the two scores are not equally well evidenced: SDR has 67 ratings behind it against 5, so its average is the more settled of the two. Written reviews point the same way: 75% of Feld Hellschreiber's written reviews are positive against 80% of SDR's.

Feld Hellschreiber ships an update every 13 months, SDR every 2 weeks. The most recent releases landed on October 8, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | Feld Hellschreiber | SDR |
| --- | --- | --- |
| Price | **$2.99** | $49.99 |
| Rating | [2.8 (5 ratings)](https://appshunter.io/ios/app/feld-hellschreiber/id650758963/reviews) | **[4.2 (67 ratings)](https://appshunter.io/ios/app/sdr-control-for-icom/id1614141094/reviews)** |
| Number of ratings | 5 | **67** |
| Positive reviews | 75.0% of reviews | **80.0% of reviews** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 13 months | **Every 2 weeks** |
| Monetization | Paid | Paid |
| Size | 4 MB | 47 MB |
| Requires iOS | **6.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPad |
| Age rating | 4+ | 4+ |
| Developer | [Black Cat Systems](https://appshunter.io/developer/301047032) | [Marcus Roskosch](https://appshunter.io/developer/334053438) |

## What reviewers say

### Feld Hellschreiber

[App page](https://appshunter.io/ios/app/feld-hellschreiber/id650758963)

This app decodes and transmits text messages using the historical Hellschreiber system, which sends characters as audio signals. It's ideal for amateur radio operators and enthusiasts interested in vintage communication methods. The app allows for both manual text entry and pre-set messages, with adjustable display contrast for optimal viewing.

**Highlights:** Decode Hellschreiber messages, Transmit text messages, Canned text message support, Adjustable display contrast, Real-time text scrolling, Audio input/output via device mic/speaker

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### SDR

[App page](https://appshunter.io/ios/app/sdr-control-for-icom/id1614141094)

Control compatible Icom transceivers remotely or locally from your iPad. Offers full operation, dual VFO, a logbook, and integrated digital modes like FT8/FT4, SSTV, and CW decoding.

**Highlights:** Remote transceiver operation, Dual VFO and DualWatch, Integrated logbook with ADIF support, FT8/FT4, SSTV, and CW decoder tools, DX-Cluster integration, Call sign lookup and map display

**In-app purchases:** none


## Frequently asked questions

### Is Feld Hellschreiber free?

Feld Hellschreiber costs $2.99, with no in-app purchases.

### Is SDR free?

SDR costs $49.99, with no in-app purchases.

### Which has better reviews, Feld Hellschreiber or SDR?

SDR is rated higher. Feld Hellschreiber averages 2.8 out of 5 from 5 ratings, while SDR averages 4.2 from 67 ratings.

### Do Feld Hellschreiber or SDR have ads?

Neither Feld Hellschreiber nor SDR shows ads.

### Which is updated more often, Feld Hellschreiber or SDR?

Feld Hellschreiber ships an update every 13 months, and SDR every 2 weeks. Most recently, Feld Hellschreiber was updated on October 8, 2026 and SDR on October 14, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*