When it comes to robotic vacuums, iRobot's Roomba line has tended to zoom to the top in Consumer Reports' tests. But a change to the Roomba's innovative way of cleaning has surprised us with a small step back for the company’s latest model, the iRobot Roomba 980, $900, in our Ratings of robotic vacuums.

In the past, the Roomba vacuums we’ve tested have all cleaned in the same pattern, randomly going over the same areas over and over again. The result, however, was consistently top-notch cleaning of carpet surfaces and bare floors.

Change of Pattern

The new Roomba 980, however, shows a change in that cleaning pattern. While this model’s navigational intelligence remains as good as ever—a plus when the vacuum is roaming among power cords and carpet fringes—this vacuum cleans in a row-and-column grid pattern. That apparently made a difference in its cleaning of carpet surfaces, scoring a notch below excellent for the first time. The top performer in our robotic vacuum Ratings, therefore, remains the older Roomba 880, $700.

The iRobot Roomba 980.
iRobot Roomba 980

While the Roomba 980 still earned our recommendation, we have a few concerns. This model is the first to offer programming and operation via an iOS or Android smartphone app. If you’re a fan of smart-home products, you might appreciate that you won't have to add another remote control to your dusty collection. But if you prefer to choose which apps go on your phone and which companies track your activities, you might prefer to have a remote—even if you have to pay an extra $10 or so. You can’t; it’s not an option.

Still, here’s a bit of perspective: Another robotic vacuum we’ve just tested, the Samsung PowerBot Essential VR2AJ9020UG, $700, allows no programming whatsoever. A first for our tests, this shortcoming means you can only set the vacuum manually whenever you need it. Compared to this, a nosy app looks pretty good.

Need a Full-Sized Vacuum?

If you’re not ready to spend up to $900 for a robotic vacuum, check out our buying guide for vacuums before browsing our vacuum Ratings of more than 140 models. Top-ranked vacuums include the Kenmore Elite 31150, $350, a bagged upright; the Hoover WindTunnel T-Series Rewind Bagless UH70120, $130, a bagless upright; and the Panasonic MC-CG937, $330, a bagged canister.