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How to choose a window cleaning robot: the glass, the grip, the rope and the backup battery, and which ranking to open

Which window robots fit your glass, how they hold on when the power fails, what the rope and the backup battery are for, and which ranking to open next.

Maciej Ziółko · RoboVerdict editorial · Published · 22 min read

A window robot is the only home robot that works against gravity, so the buying questions are different from a vacuum's: can it hold on to your glass, does it know where the pane ends, what happens in the minute after the power fails, and does it fit the panes you own. This guide takes those questions in the order a buyer meets them, using only the figures the makers themselves publish for the window robots we list. Every figure is the maker's, with the date we read it on each product page; we check nothing by hand. Where a maker publishes nothing, we say so with the label our tables use, "Not published". No prices, no judgements on cleaning quality, no hands-on claims; at the end we say which of our four rankings to open for which need.

Framed or frameless glass: what the edge sensors detect

A window robot stops at the end of a pane in one of two ways: it feels the frame with a bumper, or it senses the edge of the glass itself. Every machine we list carries edge detection according to its maker, and by our own criterion that makes each of them rated for frameless glass. That is our verdict wording, not a maker's promise, and it carries one exception: Mamibot fits edge sensors to the iGLASSBOT W100 but does not recommend it for frameless glass, and its product page says so.

The makers describe the sensing in their own terms. Ecovacs prints the frame height its sensors detect from, in millimetres. HOBOT describes sensors that react to air leaking at a window seal or at a frameless edge. Ecovacs lists both framed and frameless glass for the WINBOT W3 OMNI and the WINBOT mini 2; for its other WINBOTs it says nothing about frameless glass, and the frame-detection heights it prints are below. The figures are the makers' own, quoted as each prints them.

Glass thickness is mostly unpublished. The only figure on our product pages is the minimum of 3 mm that Mamibot prints for the iGLASSBOT W300. HOBOT writes that its robots work on glass of all thicknesses, which is a claim and not a figure.

Pane size and tilt: what the makers rate their robots for

A robot needs a pane at least as large as its own footprint plus room to turn, so every maker should print a minimum pane. Most do; only MOVA and Dreame print a maximum. We record width first, then height, in centimetres, and every figure here is the maker's.

Smallest pane

Not published for the HOBOT SP10 iScraper, the HOBOT S7 Pro, the Mamibot iGLASSBOT W200 SkyBot, the iGLASSBOT W110-DP, the iGLASSBOT W100 and the iGLASSBOT W110-P: neither maker prints a minimum pane for these.

Largest pane

A maximum tells you whether a patio door or a stairwell pane is inside the rating. Only 4 of 18 machines we list publish one, all from MOVA and Dreame, and the figures are theirs.

Ecovacs prints a minimum pane for every WINBOT and a maximum for none. HOBOT and Mamibot print neither a maximum nor, except for the W300, a minimum.

Tilted glass

A skylight or a conservatory roof is a different job from a vertical pane, and only some machines carry a tilt figure from their maker. MOVA rates the T1 Station for a tilt of up to 45°; Ecovacs prints 45° for the WINBOT W2S OMNI and the WINBOT W2S PRO OMNI and ±90° for the WINBOT W3 OMNI; HOBOT gives the SP10 iScraper a range of 7° to 100°; Mamibot prints a minimum tilt of 25° for the iGLASSBOT W100; and Dreame says the C1 Station S starts automatically between 60° and 120° and is steered by remote at other angles. The rest print no tilt figure.

Mirrors, tiles and shower screens: other surfaces

Some makers name surfaces beyond window glass, and our tables record that under "Other surfaces". It is a different question from frameless glass: a frameless pane is still glass, and whether a robot stops at its edge is settled in the section above. Of the machines we list, 8 of 18 name another surface; the words are the makers' own.

The rest name glass only: every WINBOT, the W2 PRO, W2 PRO OMNI, W2S OMNI, W2S PRO OMNI, WINBOT MINI, W3 OMNI and mini 2, the last two of which list frameless glass but no other surface; the HOBOT SP10 iScraper, which HOBOT rates for glass of all thicknesses and finishes; the Mamibot iGLASSBOT W200 SkyBot, whose page speaks of glass and smooth vertical surfaces without naming any; and the iGLASSBOT W110-DP, for which Mamibot names no other surface.

How it holds on: suction and pressure compensation

A vacuum pump presses the robot to the glass. The pascal figure a maker prints is its peak or standard-mode figure, measured its own way, so it compares two machines of one maker and not machines of two makers. Two makers also print a lower figure for the robot in motion: Ecovacs gives 2,800 Pa while moving for the W2 PRO and the W2 PRO OMNI, 3,000 Pa for the W2S OMNI, 3,200 Pa for the WINBOT MINI, 3,300 Pa for the W2S PRO OMNI and the W3 OMNI and 3,400 Pa for the mini 2; Dreame gives a sustained 3,300 Pa for the C1 and the C1 Station S. For the W3 OMNI the 10,000 Pa below is the figure on Ecovacs' Canadian specification list; its German copy prints 8,000 Pa, and we record both.

Pressure compensation means the pump adjusts suction when air leaks in at a seal or an edge. Most makers claim it; the machines without the claim are the WINBOT W2S PRO OMNI, the WINBOT MINI, the Mamibot iGLASSBOT W100 and the iGLASSBOT W110-P. Where a response time is printed it is 0.02 s for the MOVA N1 and the T1 Station and 0.04 s for the mini 2. The suction figures below are the makers' own, grouped by the figure.

When the power goes: the backup battery and the minutes the makers print

A corded robot loses its pump the moment the socket does. A small battery inside keeps the suction going for a stated number of minutes and, where the maker says so, sounds an alarm: HOBOT states one for both of its machines and Mamibot for the W100, the W110-P and, as a low-battery alarm, the W300. That figure is the maker's, and it is the one specification our safety ranking weights hardest. Ecovacs calls it power-off protection, "Ausschaltschutz" or "Stromausfallschutz" on its German pages; MOVA prints an "Absaugzeit im ausgeschalteten Zustand", and its T1 Station returns to the station with under ten minutes of battery left, keeping over thirty minutes of suction in reserve; HOBOT calls its battery a UPS and pairs it with an audio alert. Where a capacity is printed: 3,000 mAh for the W2 PRO, the WINBOT MINI and the mini 2, and 650 mAh for the W300, which Mamibot gives 25 to 30 minutes of holding; we record the 25 and do not round up.

Of the machines we list, 14 of 18 print a figure above zero. A fault self-check is a different thing, a robot testing itself before it lets go, and only the MOVA N1 states one; the T1 Station's fall lock and Ecovacs' counts of protection layers are not self-tests and are not credited as such.

Not published for the rest. Dreame claims no backup for the plain C1; for the C1 Station S its table says fall protection "yes" and gives no duration. Mamibot's page for the iGLASSBOT W110-DP prints no backup. The iGLASSBOT W200 SkyBot runs from a battery, so there is no mains supply to lose, and Mamibot prints no holding figure for it.

Ecovacs
Ecovacs WINBOT mini 2
Photo: ECOVACS ROBOTICS press kit

Ecovacs WINBOT mini 2

The slim Winbot for narrow panes from 25 × 25 cm: 8,000 Pa, felt brushes at all four corners, ultrasonic mist from a 50 ml tank for 30 m², WIN-SLAM 4.0 and 30 minutes of grip after a power cut.

8,000 PaNot published30 min backup
From
$240

The safety rope: what it is for and what the makers publish

Every machine we list ships with a safety rope, or with a cable that doubles as one. It is tied indoors to something fixed and is the last line if the suction fails. What a maker prints for it is a tensile or test load, not a promise, and we repeat the figure with the unit as printed and never convert it. Of the machines we list, 4 of 18 print a rating in kilograms.

The rest print a length, a different unit or nothing. HOBOT gives the SP10 iScraper and the S7 Pro a 4.5 m rope rated to 230 kgf, as HOBOT writes it. Ecovacs gives the WINBOT mini 2 a 3.3 m rope with a tensile rating of 1,900 N on its German page and 1,600 N on its US page; the WINBOT W2 PRO has a 6 m rope and the WINBOT MINI a 3.3 m one, with no rating printed. Mamibot prints a 5 m nylon rope for the iGLASSBOT W110-DP and a 4 m nylon rope for the iGLASSBOT W100 and the iGLASSBOT W110-P; the iGLASSBOT W200 SkyBot has a 1.5 m wire to an indoor fixture plus a suction cup on a 2.5 m extension; the rope of the iGLASSBOT W300 is combined with the power cable, with no length or rating printed. MOVA calls the rope of the N1 high-strength and prints no rating.

The OMNI models, the WINBOT W2 PRO OMNI, W2S OMNI, W2S PRO OMNI and W3 OMNI, hang on a 5.5 m composite cable to their station and carry a 1 m rope from the station's base. Ecovacs rates the station's suction cup at over 800 N; that is a suction-cup figure, not a rope rating.

HOBOT
HOBOT S7 Pro
Photo: PEARL GmbH / www.pearl.de

HOBOT S7 Pro

HOBOT's dual-mop polisher: two cloths reciprocating 600 times a minute behind a 15 µm ultrasonic spray, 4,800 Pa, ELB edge sensors, 12 cm/s, a 230 kgf rope and 20 minutes of grip after a power cut.

4,800 PaNot published20 min backup
From
≈ $490

Spray and water: tank, glass per fill and nozzles

Every machine we list except the Mamibot iGLASSBOT W200 SkyBot sprays water from a tank onto the glass ahead of the pad; the W200 SkyBot has no tank and no spray, and Mamibot describes dry wiping and wet cleaning with its cloths. The tank size and the maker's glass per fill tell you how often you refill on a large pane. The nozzle counts are the makers': six on the W2 PRO, the W2 PRO OMNI, the W2S PRO OMNI and the W3 OMNI; four on the T1 Station and the W300, and four ultrasonic mist nozzles on the WINBOT MINI and the mini 2; two pressurised nozzles on the SP10 iScraper and two ultrasonic ones on the S7 Pro. Only the MOVA T1 Station heats its water, up to 40 °C when switched on in the app, and only the WINBOT W3 OMNI washes its pads in the station.

For the Dreame C1, the Dreame C1 Station S and the MOVA T1 Station the maker's figure is not a glass area per fill. Dreame gives the C1 and the C1 Station S a cleaning cycle of 60 minutes per fill, and for the C1 Station S adds about 90 m² per station charge, not per fill; MOVA gives the T1 Station up to 90 m² of wet cleaning without saying whether that is per fill or per charge. None of them gets an area below. The tanks and the areas are the makers' figures.

Tank Not published for the HOBOT SP10 iScraper and the HOBOT S7 Pro: HOBOT prints no capacity. The W200 SkyBot has none.

How it moves and whether it reaches the corners

A round pad on a square robot leaves the corners of the pane. Makers answer with corner brushes, a scrubber that drops at the frame or a squeegee, and what we record is the claim, not the result.

Corners

No corner claim from the makers of the MOVA N1, the WINBOT W2 PRO, W2 PRO OMNI and WINBOT MINI, the HOBOT SP10 iScraper, whose Dual Glide Scraper squeegee has two replaceable blades, the HOBOT S7 Pro, which wipes with two reciprocating cloths at 600 strokes a minute, and the Mamibot iGLASSBOT W200 SkyBot, iGLASSBOT W110-DP, iGLASSBOT W100 and iGLASSBOT W110-P.

Route, obstacles and resuming

Resuming matters when a handle or a power cut interrupts the run. These machines state that they carry on from where they stopped, according to their makers:

A return to the starting point is also claimed for the Mamibot iGLASSBOT W200 SkyBot and the iGLASSBOT W110-P. Path planning is claimed by every maker except for the iGLASSBOT W100, which Mamibot gives three routes by spray direction and no pattern. Obstacle avoidance is not claimed for the HOBOT S7 Pro, the Mamibot iGLASSBOT W300 or the W200 SkyBot. Where a speed is printed it is 14 cm/s for the Dreame C1, the MOVA T1 Station and the Dreame C1 Station S, 16 cm/s for the WINBOT W3 OMNI and 12 cm/s for the S7 Pro; the others print no speed, though several print a time per square metre, quoted on their product pages as the maker's.

Cord or battery with a station

A corded robot hangs on a cable to a socket. A cordless one, in our tables, is a robot whose job needs no socket, and 7 of 18 machines we list run from a battery. All but one carry that battery in a station the robot stays cabled to, on a 5.5 m cable, so they are not cable-free; only the Mamibot iGLASSBOT W200 SkyBot has no cable at all. Station weights as printed: 8.2 kg for the T1 Station, whose copy speaks of a 6 kg counterweight; 8.3 kg for the C1 Station S, whose copy says 6 kg; 5.5 kg for the W2 PRO OMNI, 5.2 kg for the W2S OMNI, 5 kg for the W2S PRO OMNI and 10 kg for the W3 OMNI. Mains leads, where printed: 1.8 m for the C1 and the C1 Station S, 1.2 m for the W2 PRO, the WINBOT MINI and the mini 2, and 1.8 m to the station for the W2 PRO OMNI and the W3 OMNI.

Battery, in a station or in the robot

Runtimes and capacities are the makers' figures.

  • MOVA T1 Station: 80 min of cleaning out of 110 in total, the rest a 30 min suction reserve; a 4.5 Ah battery, about 180 min to charge.
  • Dreame C1 Station S: runtime Not published. Dreame's table prints 4,150 mAh and 60 minutes and its copy 7,800 mAh and 180 minutes, so we record neither; about 90 m² per station charge.
  • Ecovacs WINBOT W2 PRO OMNI: 110 min, 4.5 Ah, about 55 m² in fast mode and 22 m² in deep mode per charge.
  • WINBOT W2S OMNI: 110 min, 4.5 Ah, about 65 and 26 m².
  • WINBOT W2S PRO OMNI: 110 min, 5.2 Ah, about 72 and 26 m².
  • WINBOT W3 OMNI: 130 min, 9 Ah, about 120 and 48 m², from a 10 kg station that also washes the pads.
  • Mamibot iGLASSBOT W200 SkyBot: 100 min from a detachable 3.35 Ah pack, 100 min to charge, up to 30 m² per charge; a 2.4 GHz remote and no app.

On a cable to the socket

Cable lengths are the makers' figures; where none is printed, the label says so.

MOVA
MOVA T1 Station
MOVA press image

MOVA T1 Station

MOVA's first window robot with a base station: 10,000 Pa, panes to 2.5 × 8 m, rated for 90 m² of wet cleaning, an 80 ml tank with warm water, corner brushes, 80 minutes off the mains, 3-year warranty.

10,000 Pa2.5 × 8 m30 min backup
From
≈ $540

Noise and weight

The pump is the noise. The decibel figure is the maker's and not measured by us. Weight matters because you lift the robot onto the glass and hold it there until the suction takes.

Noise

Not published for the WINBOT mini 2, the HOBOT SP10 iScraper, the HOBOT S7 Pro, the Mamibot iGLASSBOT W110-DP, the iGLASSBOT W100 and the iGLASSBOT W110-P.

Weight

Not published for the Dreame C1 Station S, the HOBOT SP10 iScraper, the HOBOT S7 Pro, the Mamibot iGLASSBOT W300, the iGLASSBOT W200 SkyBot, the iGLASSBOT W110-DP, the iGLASSBOT W100 and the iGLASSBOT W110-P. Footprints, where printed: the N1, the WINBOT MINI and the mini 2 are 215 mm square and 55 to 59 mm high; the rest are about 270 mm square.

What the makers leave unpublished

Every product page shows the maker's source and the date we read it, and "Not published" means exactly that, not "none". Ecovacs prints a minimum pane and no maximum, and no noise figure for the mini 2. HOBOT prints no specification table at all, so tank, weight, dimensions, noise, pane sizes and warranty are unpublished for both of its machines; we use only its English feature copy, not the figures of its Polish distributor. Mamibot prints no weight for any model and no backup minutes for the W110-DP. Dreame prints no backup minutes for the C1 and two contradicting battery figures for the C1 Station S. MOVA prints no cable length for the N1.

Two more things only some makers say. Liability insurance: only MOVA states one, for the T1 Station, worldwide for the warranty period. A release year is printed only for the T1 Station, the W3 OMNI and the mini 2 (2026), the W110-DP and the W100 (2024) and the W110-P (2022).

Warranty

The warranty terms below are the makers' own, as their pages print them.

Not published for the MOVA N1, whose page records an "up to 3 years" that comes from a Polish shop and not from MOVA, the Dreame C1, the Dreame C1 Station S, the HOBOT SP10 iScraper and the HOBOT S7 Pro.

Which page to open for which need

All the window cleaning robots we list are on one page; Ecovacs' WINBOTs have a hub of their own; and How we score sets out how every score on this site is computed.