The Fraunhofer Institute for Integrated Circuits IIS has developed a Java-based Android app that allows you to analyze wireless traffic at 868 MHz using an RTL-SDR dongle. In Europe, many wireless IOT, metering and home automation radio standards operate in the 868 MHz band.
Next to receiving, detection and recognition of the following protocls is possible: ZigBee, M-Bus, KNX RF, EnOcean Radio Protocol and s-net. The beauty is, that all traffic can be inspected at one on different protocols. This can be useful for detection of random access errors and bottle-necks or in which frequency (bands) or how active the communication on those frequencies is (RSSI-based field-strength measurement with dBm). An important application is the frequency and sprectrum planning, especially for new or densed areas like in cities or fully connected production environments. Furthermore error diagnosis, intrusion detection and interference detection is possible.
It is nice to see, that especially in Erlangen the RTL-SDR movement picks up speed again and that new applications are released.
One remark is to be said. At the moment the software, even if it was funded by the Bavarian Government (Energie Campus Nürnberg), is to this state not released as open source or downloadable via the Google Play Store for Android Devices.