PulseModem A

PulseModem A

Send & receive AX.25 APRS

40 ratings
45 reviews
Free

Details

Released
August 13, 2018
Updated
August 9, 2026

Features

Background Location Access

PulseModem A screenshot #1 for iPhone
PulseModem A screenshot #2 for iPhone
PulseModem A screenshot #3 for iPhone
PulseModem A screenshot #4 for iPhone
PulseModem A screenshot #5 for iPhone
PulseModem A screenshot #6 for iPhone
PulseModem A screenshot #7 for iPhone
PulseModem A screenshot #8 for iPhone
PulseModem A screenshot #9 for iPhone
iphone
ipad
watch
🖼️Get Icon
Icons↘︎

About

This application acts as an APRS client, enabling licensed amateur radio operators to send and receive location data and messages. It supports direct connection to the APRS-IS network or transmission via VHF amateur radio, with an optional off-the-grid mode.

✓APRS client functionality
✓Send and receive location data
✓Send and receive messages
✓Direct APRS-IS network connection
✓VHF amateur radio transmission
✓AX.25 AFSK modem for off-grid use
Show original description

What's New in PulseModem A

2.0.7

August 9, 2026

PulseModem A has been completely rewritten from the ground up in SwiftUI with new icon. This is the biggest update since the app launched. CHATS Direct contacts between your callsigns and others will show up as a messenger interface. REBUILT FROM SCRATCH The entire app is now native SwiftUI on iOS 17, replacing the original Objective-C codebase. It is faster, lighter, and requires no third-party networking or UI libraries. Also beacon mode now updates your positions automatically for a set period of time. NEW: MIC-E DECODING PulseModem A now decodes Mic-E packets — the compact format used by most Kenwood and Yaesu hand-held radios. Stations that previously appeared in the feed but not on the map will now show up correctly. NEW: COUNTRY FLAGS Every station now displays the national flag for its country of origin, resolved automatically from its callsign prefix using the standard cty.dat database. NEW: REAL APRS SYMBOL ICONS Stations are now drawn with authentic high-resolution APRS symbol PNGs rather than generic placeholder icons. Over 160 symbols are included — cars, hikers, weather stations, digipeaters, ships, aircraft, and more. NEW: GPS BEACONING Send your location to the APRS network directly from the app. Your position appears on the map immediately after sending, without waiting for an echo from the server. NEW: VISUAL SYMBOL PICKER Choose your station symbol from a searchable grid showing every available APRS icon with its name and preview — no more typing two-character codes. NEW: iPad SPLIT VIEW On iPad, the Stations tab now shows a side-by-side master-detail layout. Select a station on the left and see full details, map, and QRZ lookup on the right. NEW: QRZ LOOKUP Tap the globe icon on any station detail page to look up the callsign on QRZ.com — displayed inside the app with no browser switch required. NEW: BUILT-IN HELP A new Help tab covers Getting Started, APRS basics, connecting to APRS-IS, and how to send a beacon — all in a clean, readable format. SEAMLESS UPGRADE Your callsign and passcode from the previous version are read automatically from the same Keychain entry — no need to re-enter credentials after updating. AUTO-CONNECT FIX Auto-connect on launch now correctly waits for a GPS fix before connecting, ensuring the APRS-IS location filter is always set before packets start flowing.

More

User reviews

Can’t decode from Mic

Used to use this to decode packets from my HT via the phone microphone, but that capability seems to be gone now. So without the one single thing I need it for, this app is just wasted storage on my iPhone now. Really sucks.

Good

👍👍👍👍👍

Brilliant ☝️😎

Wonderful update ☝️😎

No RF?

Very disappointed that such a well laid out app, easy to understand, and many easy to access functions…does not do RF? What’s the point of APRS and Ham Radio, if you can’t use a RADIO???

Connexion aprs.fi

Error network.nwerror 65554 nousuchrecord

Developer apps

FAQ

What does PulseModem A do?

PulseModem A is an APRS client that allows licensed amateur radio operators to send and receive location data and messages. It facilitates communication through the APRS-IS network or via VHF amateur radio transmissions.

How can I send and receive APRS data with this app?

You can send and receive APRS data in two primary ways: directly to the APRS-IS Network, or by transmitting via amateur radios that support the VHF Band at 144MHz. The app also includes a full AX.25 software AFSK modem for off-the-grid operations.

Is PulseModem A free to use?

Yes, based on the provided information, PulseModem A is available for free. There are no mentions of subscription fees, in-app purchases, or advertisements.

What are the benefits of using the off-grid mode?

The off-grid mode utilizes a full AX.25 software AFSK modem, meaning you can send and receive APRS data without an internet connection. This is ideal for situations where internet access is unavailable or unreliable.

Who is the target audience for this application?

This application is designed for licensed Amateur Radio operators. It provides them with the tools to engage with the APRS digital communication protocol for exchanging location and message information.