Here's how the 'unlimited' plans from Verizon, AT&T, Sprint, and T-Mobile compare

Everything old is new again, and unlimited data plans are back in vogue.

After months of tweaks and updates, the unlimited plans from all four of the major mobile carriers in the US seem to be in a relatively stable place.

But, per usual, all of those plans still come with a significant slate of caveats.

So to help you sort through the fine print, here's a quick rundown of how this revived set of unlimited plans match up.