Does the S7 Pro's auto-pathing actually eliminate missed strips on standard windows?

Not entirely, on its record. Independent testing found the HOBOT S7 Pro left lightly soiled glass clear with no missed spots on framed and frameless panes, while another test watched it stall a few centimeters from the top of a pane and need restarting. Its record also notes that dirt and droplets on the edge sensors cause navigation glitches. The HOBOT 2S follows a preprogrammed zigzag route, and the Hobot R3 halts at the frame and repositions.

For corner coverage specifically, does the R3's rotating pad mechanism outperform the 2S?

The records conflict. The Hobot R3 record claims its rotating pads reach corners better than fixed-pad designs, but a hands-on test found its corners left dirty because of the body's shape. For the HOBOT 2S, one hands-on review found the pads cover right up to the edges, while an owner reported it skipping the top of the window. Which of the two cleans corners better is not verified on these records.

How is the HOBOT 2S powered, and what limits multi-window sessions?

The HOBOT 2S does not run on battery between windows. It is mains-powered through a permanently attached 5 m cord, and its 20-minute figure is a backup battery rather than an operating runtime. The practical limits for multi-window sessions are elsewhere: each pane needs the unit placed and started by hand, the safety rope tied to a fixed object indoors, a socket within 5 m, and the single water tank refilled by hand on larger jobs.

Which robot is most portable for users without outdoor power access?

All three are mains-powered and corded, so each needs a socket within cord reach, which can be indoors. The HOBOT 2S has a 5 m cord, the Hobot R3 a 4 m cord, and the HOBOT S7 Pro a 4 m cord extendable to 8 m. Each lists a 20-minute backup battery; the R3 and S7 Pro records describe it as holding the robot on the glass after a power cut, not a cordless mode. The R3 weighs 2.1 lb, the 2S 2.9 lb and the S7 Pro 3.7 lb.

Do any of these robots work on frameless glass facades?

Two of the three records include frameless glass. The HOBOT S7 Pro is rated for framed and frameless glass, and independent testing confirmed it works on frameless panes. The HOBOT 2S detects the air leak at a seal or a frameless edge, so its record covers frameless glass as well as framed. The Hobot R3 record lists frameless or curved tempered glass as a poor fit, with frequent incorrect repositioning. Structural glass facades are not addressed on any of these records.

Comparisons · Robot Window Cleaners3 robots · checked 2 Oct 2026

A situation

Complete coverage or skipped strips: which window robot finishes the pane?

A pane is finished when the robot has covered the middle, the corners and the strip at the edge. The question is how each one runs its route and what reviews found left behind.

This page checks

RouteThe pattern the maker describes
CornersWhether the corners get reached
Edge stripWhat testing found left at the edge
Cord reachHow far from a socket it can work

HOBOT

IIAssistedLimited

$349list

Where to buy

Amazon

Sep 2021HOBOT-2S window cleaning robot unveiled ahead of October 2021 US launch

HOBOT

IIAssistedCapable

$400list

Where to buy

Manufacturer Amazon

Nov 2023Bearing wear pattern surfaces in year three owner reports

HOBOT

S7 Pro

IIIConditionalCapable

$460list

Where to buy

Amazon

Nov 2025Owner reports document mop pad wear patterns and edge coverage limits

Full specifications14 figures on record · 11 differ

Figure

S7 Pro

List price

2S$349

R3$400

S7 Pro$460

Released

2SOct 2021

R3Apr 2023

S7 ProMay 2025

Power

2SMains-corded, 5 m cord

R3Mains-corded

S7 ProMains-corded, 4 m cord extendable to 8 m

Smallest pane

2S15.7 in

R3Not on record

S7 Pro19.7 in

Safety rope

2S331 lb

R3441 lb

S7 Pro507 lb

Cleaning width

2S9.4 in

R3Not on record

S7 ProNot on record

Weight

2S2.87 lb

R32.1 lb

S7 Pro3.7 lb

Battery type

2SLi-Po

R3Li-ion

S7 ProLi-ion

Adhesion

2SNot on record

R33,000 Pa

S7 Pro4,800 Pa

Noise

2S64 dB

R366 dB

S7 ProNot on record

Navigation

2SEdge-Leakage Sensor: pneumatic edge detection at the window seal and on frameless glass, with a preprogrammed zigzag route, horizontal then vertical; no mapping or vision-based navigation

R3Vacuum-based edge detection with dual rotating pad cycles

S7 ProEdge detection with auto-pathing on framed windows; tether-guided positioning.

Connectivity

2SNot on record

R3Bluetooth

S7 ProNot on record

Size

2S9.45 × 9.45 × 3.39 in

R311.6 × 5.8 × 3.7 in

S7 Pro10.4 × 10.3 × 3.5 in

The same on all three

Backup hold

2S20 min

R320 min

S7 Pro20 min

Add a robot24 robot window cleaners on record + Add a robot24 robot window cleaners on record

Some links earn Robovations a commission. Nothing on this page is ranked by it.

Pane by pane

Does the robot finish the whole pane

The 2S and S7 Pro run a zigzag, horizontal then vertical. The R3 moves horizontally from top to bottom. HOBOT claims 80% corner coverage for the 2S. A lab review found the R3 cannot reach corners and left a 0.08 in (2 mm) strip at the edge. A review of the S7 Pro found small marks, mostly at edges.

HOBOT2S

HOBOTR3

HOBOTS7 Pro

1Route it runsAs the maker describes it

2SZigzag, then vertical

HOBOT describes route planning with zigzag patterns. The US store lists "Zigzag then N-way".

HOBOT product pages

R3Horizontal, top to bottom

Page says it moves horizontally from top to bottom. A Dec 2023 review says it climbs to the top first, then crabwalks down.

HOBOT product page

S7 ProZigzag, then vertical

HOBOT says it cleans "without missing a spot".

HOBOT product page

2Corner reachDoes it get into the corners

2S80% claimed

HOBOT claims an 80% corner coverage rate with an extended cleaning cloth. No independent figure found.

HOBOT product page

R3Corners not reached

Jul 2025 lab review: it "simply can't reach them due to its design". HOBOT's page says nothing on corners.

Independent lab, Jul 2025

S7 Pro

Not found

HOBOT's page lists silicone bumpers and roller-assisted turning. No corner figure found.

HOBOT product page

3Left at the edgeWhat hands-on testing found

2SPads reach edges

A Sep 2021 review says the pads "cover right up to the edges". Reader comments on it report streaks.

Hands-on review, Sep 2021

R30.08 in strip left

Lab review: it left a 0.08 in (2 mm) strip at the edge. A Dec 2023 review finished frames, edges and corners by hand.

Independent lab, Jul 2025

S7 ProMarks at edges

Jun 2025 review: small marks remained, mostly at the edges. A large window needed three passes.

Hands-on review, Jun 2025

4Cord reachDistance from the socket

16ft (5 m)

HOBOT product page

13ft (4 m)

HOBOT product page

S7 Pro

13ft (4 m)

HOBOT says it extends to 26 ft (8 m).

HOBOT product page

Same on all three: a built-in battery holds the robot on the glass for 20 minutes if mains power drops, and each comes with a safety rope.

The R3 has been lifted off and laid on the sill below the round pockets of dust its round pads left in the corners of its pane, while the 2S beside it works square into its own corner.

Your home

How each one fits a home like yours

Set the conditions that describe your home. Each robot answers from its own Fit Check; nothing is scored until you choose.

Fit check

Describe your home

Pick what applies. Each robot answers from its own record.

Window style

Frame style

Building height

Across what you setEach robot’s own Fit Check

2SSet a condition

R3Set a condition

S7 ProSet a condition

Window styleNot set

2SNot set

R3Not set

S7 ProNot set

Frame styleNot set

2SNot set

R3Not set

S7 ProNot set

Building heightNot set

2SNot set

R3Not set

S7 ProNot set

Everything else

Where they land among 27 robot window cleaners

Only the measures on which these three differ. The bar is the whole category; the block is the typical middle half; the tick is the median.

WeightMaker figure

2.9 lb

2.1 lb

S7 Pro

3.7 lb

2typical 2.8–4 · median 3.44.8

HeightMaker figure

3.4 in

3.7 in

S7 Pro

3.5 in

2.2typical 3–3.5 · median 3.19.4

Sources

Where every figure comes from

2S · hobot.com.tw and hobot.us 2S product pages; one hands-on review (Sep 2021)
R3 · hobot.com.tw R3 product page; one independent lab review (Jul 2025); one hands-on review (Dec 2023)
S7 Pro · hobot.com.tw S7 Pro product page; one hands-on review (Jun 2025)

Every value was read from the page named on 2 Oct 2026. "Not found" means the pages opened say nothing on that point; it never means the robot lacks the feature.

Questions

What readers ask

Does the S7 Pro's route stop missed strips?

HOBOT says the zigzag route cleans “without missing a spot”. A Jun 2025 hands-on review still found small marks, mostly at the edges, and a large window needed three passes.

Does the R3 reach corners better than the 2S?

Not on the evidence found. HOBOT claims 80% corner coverage for the 2S. A lab review says the R3 cannot reach corners. HOBOT’s R3 page makes no corner claim.

Which one can work farthest from a socket?

The S7 Pro, whose 13 ft (4 m) cord extends to 26 ft (8 m) per HOBOT. The 2S cord is 16 ft (5 m) and the R3 cord is 13 ft (4 m).

Common questions

What readers ask about this comparison.

Next up

What do robot window cleaners really cost to maintain?

Read the comparison

Comparison ID: RV–CMP–7511 · Last reviewed Jun 23, 2026 · Based on owner reports, manufacturer documentation, and firmware release notes

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