I used Locus to find a Chirp geocache (using the ANT+-manager and an ANT-adapter connected via USB-OTG).
Everything worked perfect 8)
However, if I try to connect to the Geocaching sensor (or any other sensor) without an ANT-adapter present in the system, I get just a toast message like "process interrupted". This is not very helpful, especially for less-technical-skilled users. I'd expect something like "There is no ANT-adapter available." or "Could not connect to ANT-adapter"...