Up until Facebook's recent acquisition of Instagram for $1 billion, Zynga's (ZNGA) acquisition of Omgpop, maker of the game Draw Something, for $210 million was the talk of the town.

However, soon after Zynga acquired Omgpop, the daily active user count of its top app -- Draw Something -- plateaued, and eventually started a slow decline. It is already down to around 12 million from a peak of 14.5 million and may continue its slow decline as the next shiny new social-viral-hyperlo​cal-mobile app jumps to the top of the leader board.

Draw Something becomes more social to fight dropping usage levels

This week, its makers have updated Draw Something with additional social features, which adds chat as well as Facebook/Twitter sharing to the game. It enables users to save their drawings and share them on Facebook and Twitter with short messages. This may help it increase its user base by attracting more users, who haven't downloaded it yet, through downloads driven by social discovery and also increase engagement through social network updates. Zynga's overall user base jumped to more than 280 million monthly active users following the OMGPOP acquisition. It can also cross-market its other games to Draw Something's user base, further driving user growth.

Zynga is the world's largest social gaming company with more than 280 monthly million active users. It competes primarily with other social gaming companies like Electronic Arts (EA), Playdom which was recently acquired by Disney (DIS) and other independent social gaming studios. Zynga has recently started focusing on the mobile gaming space, which is set to explode as smartphone shipments reach record highs in the coming years.

We currently have a $13 Trefis price estimate for Zynga, which stands nearly 25% above its current market price. New games account for almost half of its total value.