By using the OsmoSDR block you can take advantage
of a common software api in your application(s)
independent of the underlying radio hardware.

Depending to your hardware you may want to
install some or all of the optional dependencies:
rtl-sdr, uhd, osmo-sdr, gr-iqbal, hackrf.
(the last two is recomended).

Optional: MiriSDR, bladeRF, airspy and Dongle Pro+.
(not available at slackbuilds.org)