foursquare, social discovery, social networks, social media, local search, yelp, banjoFoursquare released an update to its Android app today with a home page that displays any friends who are checked in nearby.

The move adapts a user experience first created by social-discovery app Banjo, using Foursquare’s API. Banjo also shows users who have checked in on Facebook.

Digital privacy advocates have greeted Banjo and similar apps with some consternation.

Despite this dive deeper into social, the update boosts the Explore feature to top billing within the app. Once a tab labeled along the bottom of the screen, Explore is now a search bar across the top of the screen.

The search allows users to focus on a particular kind of venue, bringing Foursquare closer to head-to-head competition with Yelp.

The update also delivers some navigational tweaks.

Foursquare may be facing additional competition, too: Alike, an app offering features very similar to Foursquare’s Explore, said today that it had been acquired by Yahoo. It’s unclear whether the team will develop location-based mobile products for Yahoo, but it will become part of the company’s growing mobile division.