A new report suggests social gamers Zynga need to develop an all-in-one casino app to preserve Zynga Poker’s dwindling player base.

Market analysts SuperData Research have just released a new Social Casino Metrics report, which predicts social poker will generate an estimated $179m in revenue in 2015. That’s down from $204m in 2014 and SuperData believes the number will fall to $156m by 2017.

Zynga Poker accounted for 61% of 2014’s total, but the app’s users and spending have fluctuated wildly. Zynga Poker lost 44% of its player base last year, while revenue has fallen less dramatically due to the remaining players being more hardcore than casual.

SuperData believes casual social poker players are increasingly switching to all-in-one social casino apps that include a poker component, like IGT’s popular DoubleDown Casino. Zynga has a number of successful slots titles, including Hit It Rich! and the new Wizard of Oz Slots, but the report suggests an all-in-one Zynga casino product would help retain casual poker players while leaving Zynga Poker to the more hardcore players.