These apps use Wikispeedia. Some are loggers, some warn of speeding.
If you want to log the 100 signs required for registration, the logger is a good choice.
If you know more apps, they can be included here. Let someone know…
Make your own copy of the Wikispeedia Database using this daily cron. No registration needed.
Log speed limits without leaving your home. Use this Chrome Extension:
Torrent of the entire Wikispeedia database. Use python tools above to refresh it daily.