Thank you to Silviu YO6SAY for writing in and sharing with us news about the release of his iOS App called "CoronaSDR" which is a native client for receiving from rtl_tcp servers. rtl_tcp is a server program for RTL-SDRs that streams raw IQ data over a network connection.

Unlike Android, iOS does not allow third-party USB devices like the RTL-SDR to run on its devices. But you can set up an rtl_tcp server on a networked PC or Raspberry Pi in your home, and connect to the data stream with an iOS app like CoronaSDR.

Silviu writes:

CoronaSDR is a free, native iOS app that connects to an rtl_tcp server on your local network (no cloud, no subscription).

Current features
• Live spectrum + waterfall (Metal / GPU-accelerated)
• Demod modes: AM / NFM / WFM / USB / LSB / CW
• RF controls: gain, PPM, direct sampling, offset tuning, bias-tee
• Stations with tags + CSV/TSV import/export
• List/range scanning with squelch hold/skip
• Background audio + lock screen controls

Known limitations (early build)
• Built solo so far — no external testers yet
• Most real-world testing to date has been NFM and WFM
• Other modes are implemented, but I’d consider them early until more field feedback comes in

Tested with an RTL-SDR Blog V4 (R828D) on a Raspberry Pi running rtl_tcp.

I’d really appreciate detailed feedback (device + iOS version, tuner type, rtl_tcp command, mode/frequency, and steps to reproduce any issues).

 

Project page: https://coronasdr.pages.dev/

Issues/bug reports: https://github.com/s1lviu/CoronaSDR/issues