Just a day after the Android launch, Angry Birds Seasons has arrived at the iOS App Store as a free update to Angry Birds Halloween, actually replacing the latter game altogether (although your Halloween performance remains saved). For new purchases, Seasons delivers both the Halloween levels as well as the 25 new Christmas levels — which, like an Advent calendar, are meant to be played one-per-day through Christmas. In fact, developer Rovio forces you to play that way, hooking the game into a time server that only unlocks each new level at midnight PST every day. (We tried taking our Android device offline and manually changing the date on the phone, but the game apparently requires a data connection to thwart off cheaters like us.) Angry Birds Seasons is now available as standalone title for the same 99 cents as the original megahit.