Rotating drum~$599Whisker
Whisker's entry model shrinks the globe to fit a 20.6-by-24.3-inch spot and drops the curtain lasers: its own FAQ says it relies on weight sensors to know a cat is inside. The trade shows up in the ratings, which stop at two cats and 19 lb, with a 14.5-inch interior height that Whisker itself says is tight for especially tall cats.
Approx. price
~$599
maker's store, not a live price
Best for: One or two average-size cats in an apartment
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Whisker says the sensor detects cats from 3 lb. At the usual rate of about a pound a month, that means leaving automatic cleaning off until roughly 3 months. Below the threshold, a kitten may not register at all, and the box could start a cycle with it inside.
Detection: weight. The maker does not state any anti-pinch protection.
How minimum weights work, and what to do below themThe maker publishes no drawer volume, so the days cannot be worked out. Its own claim is up to 7 days for one cat.
The two lists above are drawn from the maker’s own pages, manuals and prices, not from owner reports. Where owner discussion has been read it appears in its own section below, so the two are never mistaken for each other.
The EVO is the newest and smallest Litter-Robot. Owner discussion of it is dominated by one hardware complaint: a waste drawer that about a dozen owners cannot get to stay flush, often because it pops open when a cat steps on the front, and which three tie to smell escaping between cycles.
Beyond the drawer, reports are the familiar mix for a new product: units that would not finish onboarding (support spoke of a bad batch), one that shed a part in its first fortnight, an app that kept showing the drawer as nearly full after it had been emptied. One owner went as far as calling it the worst purchase they had made after dealing with smeared waste daily. Others report no smell, an easy fit in an apartment, or their cats using it more than an older LR4 in the same home.
One or two cats up to its 19 lb rating, in a small space, is the brief it was designed for. Given the drawer reports, several commenters recommend the LR4 instead, bought on discount, and one owner who returned an EVO says the drawer on the LR5 they got instead stays shut.
About a dozen owners report the same thing, often the drawer popping open when a cat steps on the front. Whisker points owners to the drawer assembly steps; two grooves at the bottom must be fully pushed in. Some received a replacement drawer or base, though one found that did not solve it. Owners who fixed it added a ramp so the cats stop stepping on the drawer, or a cover over it.
Some owners think so and blame the drawer gap; one comparing directly with a relative's LR4 said the EVO needed much more cleaning to stay acceptable. Three other owners say theirs does not smell.
Whisker says kittens from 3 lb can use it automatically. One owner found it would not track a kitten of about 6.5 lb, so check the history in the app during the first weeks.
The EVO is smaller, 20.6 by 24.3 inches against the LR4's 22 by 27, and one owner says it fits their apartment perfectly. Several commenters who can fit the LR4 recommend it instead because of the EVO drawer reports and because the LR4 is often discounted.
Rotating drum
Best for: Two or three average cats in a home that already uses clay clumping litter
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Rotating drum
Best for: Large multi-cat homes that want visit-level tracking without a camera
Rotating drum
Best for: Multi-cat homes where telling similar-weight cats apart matters