Whether air purifiers can truly reduce allergies caused by larger particulates such as pollen, dust, mold, and animal dander is a bit controversial, according to the EPA.  "Most of these particles are found where they settle on surfaces in the home, rather than in the air," the EPA says. "They cannot be removed by an air cleaner unless disturbed and re-suspended in the air." Before turning to an air purifier for allergy relief, consider what type of allergies you have. Air purifiers may do a better job of capturing pet dander compared to other types of allergens. According to the American Lung Association, pet allergens "remain suspended in the air for a long time, much longer than allergens from cockroaches or dust mites." Dust mites, on the other hand, "cling to particles that are too heavy to remain in the air for long" and settle into things like pillows, bedding, and furniture "within minutes."  In my experience, air purifiers aren't an infallible cure for pet allergies, but they can certainly help. To combat dander from my dog, I usually keep at least one air purifier running 24/7. I find it particularly helpful to have one blowing clean air in my direction at night when my symptoms worsen.  Going forward, we'll continue to update this list as we review new models we deem worthy of inclusion. Check back often and, in the meantime, let us know in the comments if you want us to review any specific smart air purifiers. Editors' Note: John Delaney contributed to this article.