To test connectivity, we put the handheld unit and the camera in neighboring rooms with 30 feet between them. We looked for lag, choppiness, and changes in the video or sound quality. While we rated it separately, we also did tests to estimate each baby cam’s maximum indoor range. Each camera we tested has a range of 100 feet or more, which is enough for an average-size home.
The most important thing to look for in all kinds of baby monitors is audio quality. Regardless of whether you want a video-based baby monitor or not, you need clear audio so you can hear your baby properly. You'll also want one with sound activation so that you don't have to listen to white noise 90% of the time. With sound activation, you'll only hear the noises from your baby's room when there's something important to hear.
Once you've settled on a type and have considered your range, you can look at the potential choice and which features they have. The more budget-friendly choices usually lack bells and whistles but are still functional. If you want more features like nightlights, lullabies, and talk to the baby, then you may pay more and the unit could be more difficult to use. The one feature we think is important is sound activation to help keep your device quiet when your baby is quiet, thereby increasing your chances of a full night's sleep.