Google appears to be trialling a new Free App of the Week feature on the Google Play store.
The feature acts much the same as the Free App of the Week section on Apple's App Store. Editors on the store will offer up a new premium game or app to users each week for free.
Currently, premium game Card Wars: Adventure Time is available for free in all regions, although the Free App of the Week page isn't showing on the store.
A link to the browser version of the feature worked in the US, but has apparently been taken down. This suggests that the feature is still quietly being tested.
VentureBeat notes that the offer started fairly recently, possibly on March 17th. The first app on offer was Ultimate Guitar Tabs & Chords.
Apple has also been adding new features to its store lately. A dedicated Indie section was launched on March 16th to highlight games from indie developers.