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The Boston Planning & Development Agency has approved plans for a 14-story co-living building at Herald and Albany streets in the South End.

The 250-unit building will be the final phase of the massive Ink Block complex that has been opening for years on and around the old Boston Herald headquarters.

National Development, the developer behind the Ink Block, and Ollie, a New York concern that operates co-living spaces elsewhere in the U.S., have described the building as a “millennial resort” complete with tiny living spaces—some smaller than 400 square feet—and a suite of services that includes organized social activities.

“We’re trying to offer a friction-free style of living—the ability to show up with a backpack full of clothes, your toothbrush, and your laptop and be ready to go,” as one Ollie co-founder described it to the Globe in late 2017, when the tower was first proposed.

Will it take in Boston? Rents are certainly high enough as it is, ensuring a strong demand for just about any new development. Throw in mixers, yoga, and game lounges, and you might be at the start of a trend in Boston.