Mobile gaming was one of the hot topics at the Inside Social Apps conference held in San Francisco last week.

The event was packed with developers looking for ideas and insight to increase discovery, user engagement, and profitability for their social games, while speakers include luminaries such as Google's Eric Chu, CrowdStar's Peter Relan, ngmoco's Jason Oberfest and Playfish's Kristian Segerstrale.

Here are some highlights of the talks and bar room discussions.

1. Mobile is the new social

Most, if not all, social gaming companies are building mobile-integrated games or focusing new development exclusively on mobile platforms with fast-moving Facebook gaming outfit Crowdstar now dedicating a third of its resources to its mobile business.

2. Nowhere to hide

Facebook is officially the most downloaded free app on iPhone and has over 200 million mobile users. The majority of users still access the site via a mobile browser but Facebook is pushing apps hard and has even created a Java app for the millions of users on feature phones in developing countries.

Similarly, Sony Erickson has announced that its all new devices will be preloaded with a Facebook app and single sign-on.

3. Not if but when

Lack of in-app payments is blamed for Android's low profitability (98.4 percent of all downloads on Android are free). That said, key social companies including ngmoco consider Android a platform with major growth opportunities. After all, everyone knows that behind the scenes, Google is working hard to get such features and operator billing live.

4. Crossing over

Differences in play style and usage patterns are cited as main reasons why single social titles have not yet proven successful on both Facebook and mobile platforms. However, the company that first manages to square this circle will have hit the next great gusher of social gaming.

5. Don't forget the kiddies

With around half of OpenFeint's customers being iPod touch users, the under-13 audience should be always considered in game design. In addition, think about the differences in terms of how this audience uses and indeed treats devices. The trend of handing off your smartphone (aka the pass back phenomenon) is the primary cause of sticky iPhone games, and sticky iPhone screens.