# CoronaSDR vs C.md

The clearest difference is in-app purchases: CoronaSDR at none against C.md's 1. C.md's advantage is update cadence (every 4 days vs every 3 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. C.md sells 1 one-off in-app purchase. CoronaSDR asks for nothing beyond the download.

CoronaSDR ships an update every 3 weeks, C.md every 4 days. The most recent releases landed on October 6, 2026 and October 8, 2026 respectively.

## The numbers

| Metric | CoronaSDR | C.md |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (5 ratings)](https://appshunter.io/ios/app/coronasdr-rtl-sdr-client/id6759222137/reviews)** | — |
| Number of ratings | **5** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 weeks | **Every 4 days** |
| Monetization | Free | — |
| Size | 5 MB | 173 MB |
| Requires iOS | 18.0 | **17.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Alien Systems S.R.L.](https://appshunter.io/developer/1047123293) | [建东 高](https://appshunter.io/developer/1597492102) |

## What reviewers say

### CoronaSDR

[App page](https://appshunter.io/ios/app/coronasdr-rtl-sdr-client/id6759222137)

This application allows users to connect to and control RTL-SDR servers on their local network. It provides live spectrum and waterfall displays, various demodulation modes, and DSP controls for audio filtering and signal tuning. Users can save favorite stations and adjust RF settings.

**Highlights:** Live spectrum and waterfall display, Multiple demodulation modes (AM, NFM, WFM, USB, LSB, CW), DSP controls (squelch, AGC, filters), Station favorites with import/export, RF controls (PPM, tuner options), Diagnostics and performance pipeline

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

**In-app purchases:** none


### C.md

[App page](https://appshunter.io/ios/app/cmd-markdown-reader/id6810085356)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| C.md Pro | $9.99 | one-time |


## Frequently asked questions

### Is CoronaSDR free?

CoronaSDR is free to download, with no in-app purchases.

### Is C.md free?

C.md is free to download, with in-app purchases available.

### Do CoronaSDR or C.md have ads?

Neither CoronaSDR nor C.md shows ads.

### Which is updated more often, CoronaSDR or C.md?

CoronaSDR ships an update every 3 weeks, and C.md every 4 days. Most recently, CoronaSDR was updated on October 6, 2026 and C.md on October 8, 2026.

---

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