Halo Collar 5 GPS Wireless Dog Fence, Orchid

Why it's worth it

Halo is the only pick that tries to keep your dog home rather than just tell you where he went. It draws GPS fences you can place almost anywhere, then warns your dog with sound, vibration and optional static as he gets close to the line.

This is a containment system first and a tracker second. You draw boundaries on a map — around the yard, the trailhead, the neighbor's chicken coop — and the collar handles the rest with a tiered warning: a tone, then vibration, then an optional static correction. For a digger or a fence-hopper, that's a different job than a dot on a map, and it's the one that keeps the dog in the yard.

The positioning hardware is the most serious here. Halo says the collar combines dual-frequency L1 and L5 satellite signals with real-time corrections from ground stations for accuracy within about two feet, and updates position twenty times per second. Boundary accuracy matters more than tracking accuracy. A fence that wanders ten feet either way teaches your dog nothing except that the rules are random.

From our review of 7 pet gps trackers and smart collars, by James Bennett, Associate Editor

What we like

• +This is a containment system first and a tracker second
• +The positioning hardware is the most serious here
• +There's a training program built in, developed with Cesar Millan, and you should plan on using it

What to know

• –Halo needs cell or Wi-Fi coverage to do most of its work, and owners in thin-signal areas say so loudly
• –App reliability is the other recurring gripe — connection errors, slow loading, the occasional lockout