LA TIMES - May 18 - Online dating through smartphone apps is driven mainly by photos and proximity. There are about a dozen smartphone apps which use location-based GPS technology to allow people to connect at public venues. The apps facilitate real life meetings in places of common interest. While most apps are free to download and use, many offer subscriptions for premium features at around a few dollars per month. Mark Brooks, a consultant to online dating services, said premium levels could eventually be a significant source of income for the apps but only after they reach a critical mass of users.