The power level in ranked

After having played a few matches:

It seems as though you need the majority (75%+) of the Splat Zone. You definitely do not need anyone in it; I took many from overhead. Taking a Splat Zone means that the whole thing will briefly turn to your ink color, entirely (so if it was, say, 95% your ink, it will now be 100%).

If the zone is currently controlled by the opposing team, when your team covers around 50% of the zone, it will become neutral again so that if either team reaches around 75% coverage, it will fully change (back) to that team's color.

If the control switches from one team to the other, the previous holding team will have time added to their timer so they will have to hold the zone for a longer amount of time if they capture it again. The amount of time added is greater if the current time remaining is low and if the zone was continually held for longer. This extra time is separate from the main score and doesn't count when determining the winner.

All maps have either one or two splat zones. In maps with two zones, control of each zone is the same as usual, but the timer will only count down for a team when that team controls both zones.

According to one article, they used their phone as a hotspot and found that it used about 150Mb of data an hour. (actually 153 to be more precise).

A Redditor reported yesterday (July 23, 2017) a few sources stating about 135-160Mb an hour. It appears that you can expect about this much data to be used an hour.