You can check real time traffic info in Japan. Not only highways but also local!
This application displays real time traffic conditions in Japan which are released by JARTIC.
This has Japanese and English UI. If you want to switch them, uninstall once, change locale of your Android and install again, please.
JARTIC updated their web site on 2012/Oct/1st, and version 1.x of this app doesn't work.
That problem is solved version 2.x. Please update it.
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