These pages do not bake cookies. I'll let you know when they do.
The free versions of Hellbreak and War Pigeons will soon use Google AdMob, which collects info for ads personalization. Everything will be under srandard Google rules and this section will be expanded to cover proper detail before releasing the games with ads.
After login to Apple Game Center all the games send player progress to Apple.
All other data remain on the device in the app and are not shared with anybody.