I just bought one UAP-AC-PRO. The one pack comes with a PoE injector. The five pack does not. I highly recommend it after a week of use.

Also, the linked article is wrong. The iphone app is more than adequate for simple home setups (no crazy java pc installation required while you're up on a ladder / in the attic installing it). It wouldn't surprise me if they have a comparable android app. Didn't check.

Also Ubiquiti are launching a new mesh networking product this month.