Comparison

iSDR vs Morse Code

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

Head to head
About

iSDR

This app allows experimenters and amateur radio enthusiasts to build a portable software-defined radio receiver using their iOS device. It processes radio signals using the device's processor and offers various display and filtering modes. Additional hardware is required for live signal reception.

Highlights
  • Six receive mode settings (USB, LSB, CW, AM, FM, Binaural)
  • Selectable bandwidth settings
  • 120 dB dynamic range signal strength meter
  • Three AGC settings (fast, slow, off)
  • Spectrum, Waterfall, and Oscilloscope display modes
  • Supports downloaded audio-format spectrum files via iTunes
  • Embed center frequency in file names for automatic display
Features
Read full description

PLEASE READ THE ENTIRE DESCRIPTION BEFORE PURCHASING. iSDR is the first and only software-defined radio application compatible with the Apple iPhone®, iPod touch® and iPad™. iSDR is for experimenters and amateur radio enthusiasts looking to construct a truly portable software-defined radio receiver. Additional hardware is required to receive live signals. Currently, iOS devices will not work with RTL-SDR USB dongles, and they are not supported by iSDR. PLEASE NOTE: Receiving live on-air signals using iSDR requires purchasing or constructing a "quadrature sampling detector (QSD)" RF front-end device, and connecting it between an antenna and the microphone input jack. Alternatively, iSDR can be used to implement a panadapter for use with a compatible radio receiver. Without a QSD RF front-end or a connected radio, iSDR will only play I/Q recordings of actual radio signals. Additional recordings can be loaded into the app using iTunes file sharing - some recordings are available free to download from the Internet. Visit the support web site for more information. iSDR includes a sample I/Q recording featuring 30 seconds of a ham radio contest. This is for demonstration purposes only. It is not meant to fool you! It is to allow you to experience how the app works without having to do anything yourself: just turn it on. You can download and play your own files if you like. Please see the support page for details. AND PLEASE contact us directly if you experience any issues with using this app. We will respond promptly when provided with details. When iSDR is used to receive live radio signals, receiver performance will depend largely on the quadrature sampling detector and antenna that you use. iSDR is a software-defined receiver application for use on mobile handset devices and iPad. Despite its extreme portability, the app utilizes the same digital signal processing techniques found in PC-based SDR receivers. It does frequency domain filtering using a theoretical "brick wall" sinc filter algorithm to provide steep and deep bandpass filtering. iSDR doesn't utilize any DSP hardware but instead uses the iOS device's processor to implement DSP algorithms. Features o Six receive mode settings: USB, LSB, CW, AM, FM* and Binaural. o Selectable bandwidth settings for each mode. o Signal strength meter covering 120 dB of dynamic range with peak and average power indication. o Three AGC settings: fast, slow, and off. o Three display modes: Spectrum, Waterfall and Oscilloscope. o File sharing** supports downloaded audio-format spectrum files synced using iTunes. o Most PCM file formats are supported, including .wav and .caf. o Embed the center frequency in your file names and iSDR will automatically display the correct frequency! o Tune quickly using a single touch to the display screen, or tune precisely using the rainbow tune bar. o Change radio settings with a simple double-tap action to the red cursor, mode text, AGC indicator or signal grid! o Up to 44.1 kHz of available spectrum bandwidth. o Dimmable semi-log or linear spectrum grid (native Settings app only). o Adjustable CW offset (native Settings app only). o Monaural microphone input automatically adjusts the display to 22 kHz bandwidth. o Automatically detects if external audio is available for receiving live signals (menu selectable). o Reverse I/Q stereo input logic (menu selectable). *FM mode is not supported for monaural signals, and will not appear as a mode selection unless stereo audio (live or recorded) is available. Narrowband FM only: 16 kHz or 11.2 kHz bandwidth. Please contact Digital Confections with your questions and suggestions!

About

Morse Code

Learn and master Morse code with this app. It features AI-powered audio decoding, interactive practice games, and a comprehensive code table. Customize your learning experience and track your progress.

Highlights
  • AI audio decoding
  • Practice games
  • Morse code table
  • Bidirectional translation
  • Customizable settings
  • Progress tracking
Features
Read full description

Morse Master helps you learn Morse code by ear with a structured Koch-method path and practical CW drills. Instead of memorizing dots and dashes from a chart, you train the sound patterns used in real copying and sending. Training: - Progressive Koch lessons that introduce characters step by step - Daily Sprint sessions for focused 60-second practice - Listening and receive drills for Morse copy - Sending practice for rhythm, timing, and keying control - Weak-character review and confusing-pair drills - Adjustable WPM, Farnsworth spacing, pitch, noise, and fading - WPM Ladder, Free Range, and copy practice for extra reps Signal tools: - Text to Morse and Morse to text, including Russian, Greek, Japanese Wabun, and Chinese telegraph code - On-device audio decoding from recordings or microphone input - Flashlight Morse transmitter - Training history, progress, badges, and weak-character review Beyond the app: - Morse keyboard: type in Morse in any app, with one-key or two-key input - Apple Watch: check your progress and run listening drills on your wrist; results sync back to iPhone - Home Screen and Lock Screen widgets for today's Sprint, your streak, and due reviews - iCloud sync across your devices (PRO) Morse Master works offline, has no ads, and does not require an account. It is built for beginners, ham radio learners, and CW operators who want a clear daily path from first sounds to steadier copy and sending. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://morsecodetrainer.vercel.app/privacy

Screenshots

iSDR4 screens
Morse Code4 screens

Verdict

The call

The clearest difference is price: Morse Code at Free against iSDR's $0.99. Morse Code also leads on rating (4.6 vs 2.5) and update cadence (every 5 days vs every 3 months). iSDR's advantage is iOS requirement (9.0 vs 15.0). On ads and in-app purchases 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

Morse Code is free to download; iSDR costs $0.99 up front. iSDR sells 1 one-off in-app purchase and Morse Code sells 4 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Morse Code holds the better App Store score, 4.6 against 2.5. That said, the two scores are not equally well evidenced: Morse Code has 242 ratings behind it against 11, so its average is the more settled of the two. Written reviews point the same way: 52% of iSDR's written reviews are positive against 69% of Morse Code's.

UpkeepUpdate frequency

iSDR ships an update every 3 months, Morse Code every 5 days. The most recent releases landed on October 4, 2026 and October 13, 2026 respectively.

Scorecard8 real differences · 2 level
iSDR versus Morse Code: the parameters behind the verdict, then further details
ParameteriSDRMorse Code
Price$0.99Free — better
Rating2.5 (11 ratings)4.6 (242 ratings) — better
Positive reviews51.7% of reviews68.6% of reviews — better
Number of ratings11242 — better
Update frequencyEvery 3 monthsEvery 5 days — better
AdsNoNo
In-app purchasesYesYes
MonetizationPaidFree with in-app purchases — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod, Mac, Apple Watch — better
Requires iOS9.0 — better15.0
Further details — not scored
Size36 MB46 MB
Age rating4+4+
DeveloperDigital Confections LLC亚娟 秦

Customer experience

iSDR

All ratings11 ratings
Positive36.4%
Neutral0.0%
Negative63.6%
Written reviews58 reviews
Positive51.7%
Neutral12.1%
Negative36.2%

Morse Code

All ratings242 ratings
Positive89.7%
Neutral4.5%
Negative5.8%
Written reviews35 reviews
Positive68.6%
Neutral11.4%
Negative20.0%

In-app purchases

1 purchases

iSDR

One-time1
  • Wi-Fi Radio ControlFree
4 purchases

Morse Code

Subscriptions2
  • Morse Master PRO Monthly$0.991 Month
  • Morse Master PRO Annual$2.991 Year
One-time2
  • Unlock full version$0.99
  • Morse Master PRO Lifetime$4.99

Questions

Is iSDR free?
iSDR costs $0.99, and also offers in-app purchases.
Is Morse Code free?
Morse Code is free to download, with in-app purchases available.
Which has better reviews, iSDR or Morse Code?
Morse Code is rated higher. iSDR averages 2.5 out of 5 from 11 ratings, while Morse Code averages 4.6 from 242 ratings.
Do iSDR or Morse Code have ads?
Neither iSDR nor Morse Code shows ads.
Which is updated more often, iSDR or Morse Code?
iSDR ships an update every 3 months, and Morse Code every 5 days. Most recently, iSDR was updated on October 4, 2026 and Morse Code on October 13, 2026.

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