When is the first time a card can tap without haste? On my next upkeep or my opponents upkeep?
Example {Krenko, Mob Boss}
Your next turn
A card can use an ability that requires tapping as part of its cost after the turn it could attack, essentially. So after it has continuously been under your control since the start of one of your turns.
107.5. (http://imtgapp.com/forum/index.php?action=imtg;area=rule;number=107.5.): The tap symbol is {T}. The tap symbol in an activation cost means "Tap this permanent." A permanent that's already tapped can't be tapped again to pay the cost. A creature's activated ability with the tap symbol in its activation cost can't be activated unless the creature has been under its controller's control continuously since his or her most recent turn began. See rule 302.6.
RESOLVED
We should specify here: CREATURES are under that clause.
Artifacts may be tapped after they enter the battlefield.
Same with land