this is fun, a little searching on the web and you find a whole swag of amateur radio related apps for iPhone and Android, even a couple found for Symbian.
but w.r.t. Android there are lots of goodies, as for the apps that interested me at this time,
some on sources such as Android Market and Android Zoom, here they are:
EchoLink Node Finder - using Google maps, will show EchoLink nodes in your vicinity or any specified location. You can select a tag on the map and it provides the info about that node.
EchoLink - an Echolink client, for making connections to Echolink Repeater and Link nodes. You can operate from your phone, just like a desktop operator do.
IRLP Node Finder - using Google maps, will show IRLP nodes in your vicinity or any specified location. You can select a tag on the map and it provides the info about that node
APRS Viewer - using Google maps you can show APRS nodes near you location or other specified locations.
APRSdroid - an APRS tracker for sending position reports, with basic receive of local stations.
And several apps like logbook, satellite tracker, etc.