One of the very best things about the second-generation iPhone — known as the 3G — was the GPS functionality. Of course, it wasn’t as full-featured as a dedicated unit you could get from Garmin or TomTom, but it still beat the heck out of Mapquest.

Well, now the TomTom has come to the iPhone. A $99 application, it’s far from the cheapest program you can buy for your phone, but it may be one of the most useful.

The  TomTom for iPhone takes care of most of the built-in GPS’ weaknesses. The two most glaring are turn-by-turn navigation and voice directions. It also adds TomTom-only features like TomTom IQ Routes, which the company says finds the quickest, most efficient route to a destination.

Initial reviews of the app are positive for the most part. Some of the drawbacks listed by users include no spoken street names, and it lacks traffic updates. On the whole, though, most users seem quite happy with this app. Expect TomTom to update this software frequently (and for a hundred bucks, they should!), adding some of those missing features.