You may have missed the first 6 days but there’s still plenty of time to enjoy. Get free App Store games in the run up to Christmas from the Appvent Calendar. The promotion is run by developer Blacksmith Games and will feature a free game each day until December 22nd. December 23rd and 24th will have ‘other great surprises’ instead of a free game!
They’re free and it’s a great way for small indie developers to get some exposure for their apps. Each game is free for a single day only so keep checking back!