What's New

Bug fixes and performance enhancements

App Description

An RTL-SDR Software Defined Radio receiver app for iOS devices.  Listen to AM, FM, SSB and CW radio signals. View an RF spectrum and waterfall. Connect, via the rtl_tcp network protocol, to networked RTL-SDR USB peripherals.

This app requires an external rtl_tcp server. iOS devices do not currently support the direct connection of USB peripherals such as an RTL-SDR. Thus, the use of this app requires network access to a server, such as a Raspberry Pi (or Mac), with an RTL-SDR unit plugged into its USB port, and running the rtl_tcp protocol at an TCP/IP network address accessible from your iOS device. This allows a Raspberry Pi (or Mac) to act, essentially, as the USB port adapter for your iOS device. The rtl_tcp SDR app can also connect to hfp_tcp for the Airspy HF+, rsp_tcp for SDRPlay devices, and lmm_tcp for the LimeSDR Mini; see GitHub for server source code. This app can also connect directly to a networked Hermes Lite 2 QRP SDR transceiver, no server required.

No support is provided for installing any of the rtl_tcp or other tcp software needed to use this app (with a Raspberry Pi, or otherwise). Please do not download this app unless you are already familiar with Software Defined Radio, have an RTL-SDR or equivalent USB SDR peripheral, and have already installed and tested rtl_tcp on your Raspberry Pi, Mac, or other server. Note that this app requires a very high bandwidth network connection in order to receive streams of real-time RF samples from an RTL-SDR. It is recommended that your rtl_tcp server be on a wired connection rather than on the same WiFi as your iOS device.

iPhone Screenshots

(click to enlarge)

rtl_tcp SDR screenshot 1 rtl_tcp SDR screenshot 2 rtl_tcp SDR screenshot 3

iPad Screenshots

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rtl_tcp SDR screenshot 4 rtl_tcp SDR screenshot 5

App Changes

  • April 29, 2018 Initial release
  • June 14, 2019 New version 1.2.2
  • August 17, 2019 New version 1.2.4
  • August 29, 2019 New version 1.2.5
  • September 25, 2019 New version 1.2.6
  • October 03, 2019 New version 1.2.7
  • December 24, 2019 New version 1.3.2
  • July 15, 2020 New version 1.3.6
  • November 12, 2020 New version 1.3.7
  • September 16, 2023 New version 1.4.8