The Yelp iPhone application (free) allows users to sync up with their Yelp web account. Though you can't actually review a site or interact with other users within the application, you can read other users' reviews, bookmark businesses, get directions, add photos, and do broad or location-based searches. Conveniently, it also remembers your 10 most recently accessed businesses for easy recall.
The application is fast and a breeze to use. It is very useful for quickly locating and evaluating local businesses. Hard core Yelp-ers may be disappointed in the lack of social features--you can't write reviews or respond to other's reviews via the iPhone. Me? I wouldn't want to write a full review of a business on the iPhone keyboard, and I would even venture to say that reviews written in that manner would probably lack the wit and
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