ISINWHEEL S4 vs JETSON Relay - Which Kid's E-Scooter Actually Deserves a Spot in Your Garage?

Fast Answer for Busy Riders ⚡ (TL;DR)

The ISINWHEEL S4 edges out the JETSON Relay overall: it feels more complete as a kids' e-scooter, with stronger performance, richer features and a generally more confidence-inspiring package for young riders.

The JETSON Relay makes sense if price is tight, your child is on the lighter side, your streets are billiard-table flat, and you just want a very simple "first taste of electric" that folds tiny and weighs next to nothing.

If you want something that kids will stay excited about for longer, and that copes better with real-world terrain and rider weight, the S4 is the safer bet.

Stick around for the full breakdown - the differences are subtle on paper, but they feel huge once the wheels start turning.

Kids' scooters used to be simple: two wheels, a wobbly aluminium tube, and a guarantee of grazed knees by dinnertime. Now we have LED light shows, Bluetooth speakers, digital dashboards and safety systems that would make an entry-level commuter scooter blush.

The ISINWHEEL S4 and JETSON Relay sit right in the middle of that new landscape: compact, child-sized electric scooters promising just enough speed to feel exciting without turning your local cul-de-sac into a MotoGP grid. I've put real kilometres on both with a rotating cast of test riders (read: kids who never say no to free scooters), and they target a nearly identical age and price bracket - but they go about it in quite different ways.

The short version: the S4 feels like a shrunk-down "real scooter" that happens to be kid-friendly, while the Relay feels more like a clever electric toy that's trying to be a scooter. Let's dig into where each one shines - and where the marketing gloss starts to crack.

Who Are These For, and Why Compare Them?

Both scooters are firmly in the "first e-scooter" category: pre-teens, mostly suburban terrain, parents hovering nearby pretending not to hover. The ISINWHEEL S4 officially stretches from younger school kids up to early teens, while the JETSON Relay focuses more on late-primary school children who have already mastered a manual kick scooter.

Pricewise they live in the same neighbourhood, the kind where you think twice before buying, but not three times. Neither is a school-run workhorse or something you'd want an adult to commute on. Instead, they are for park laps, neighbourhood exploring, and those endless figure-of-eight runs in front of the house.

They compete because parents almost always cross-shop them: both are light, both fold, both have kick-to-start safety and solid tyres, both offer multiple speed modes and similar claimed ranges. On paper, choosing between them looks like splitting hairs. On the road, the distinctions are much clearer.

Design & Build Quality

Pick up the ISINWHEEL S4 and you instantly get "mini commuter scooter" vibes. The aluminium frame feels reassuringly solid, the stem doesn't twist like warm liquorice, and the deck has proper width and a rubberised surface that doesn't scream "toy aisle". The integrated LED dashboard and deck lighting are neatly executed rather than slapped on as an afterthought, and cabling is reasonably tidy for this class.

The Jetson Relay, by contrast, shows more of its budget roots when you handle it. The frame is still aluminium, but tolerances feel a bit looser: you notice a hint more play in the stem and a general lightness that is great for carrying, slightly less great for long-term solidity. The deck is narrower and more basic, and the cockpit - throttle plus tiny LED readout - is functional but sparse. It's not a disaster; it just feels built to hit a price, not to impress anyone who's ridden a "proper" scooter.

Design philosophy reflects that. The S4 leans into the "premium toy" angle with colourful finishes, glowing deck strips and Bluetooth speakers - the kind of things that make kids' eyes light up and parents quietly hope there's a volume limit. The Relay goes the minimalist route: decent colours, simple lines, no party tricks. Think "starter pack" rather than "centre of attention".

In the hands, the S4 simply feels the more substantial, better-finished machine. The Relay earns points for being featherlight and compact, but it does feel built to a cost - which, to be fair, it is.

Ride Comfort & Handling

Neither of these is a magic carpet. Both roll on small solid wheels with zero suspension, which on real-world pavements is a polite way of saying: tell the kids to avoid potholes and tree roots.

The ISINWHEEL S4 has a slight edge here. Its wheels are a touch larger and the deck sits low and planted, so it feels more stable at its modest top speed. The deck is long enough for kids to find a natural stance, and the scooter's overall heft actually helps it track straighter over rough patches. On decent asphalt, it's smooth and confidence-inspiring. On cracked sidewalks you feel the chatter through your knees, but it doesn't get skittish unless you really provoke it.

The Jetson Relay rides more like a nimble feather. Its very low weight makes it responsive, but also more easily unsettled by imperfections. Small cracks and pavement seams that the S4 shrugs off tend to tap the Relay's tiny wheels on the nose. After a few kilometres of bumpy sidewalk, most kids will still be smiling - but they'll know exactly what the surface looked like, because they've felt every centimetre of it.

Handlebar height adjustability is decent on both, and both offer a comfortable upright posture for their intended age brackets. The S4's slightly broader bar and firmer stem clamp combine to give more steering confidence, especially for nervous younger riders. The Relay's leaner bar setup emphasises agility over rock-solid feel - fun on smooth paths, a bit twitchy on rougher ones.

For pure comfort, they're in the same league, but the S4 is more forgiving and less fatiguing over longer play sessions, especially on mixed-quality pavements.

Performance

This is where the character differences really pop.

The ISINWHEEL S4 has a motor that, in a kids' context, qualifies as "properly lively". For light riders it pulls away with enough urgency to feel exciting without ever yanking the bars out of small hands. The three speed modes are genuinely useful: the slowest is walking-pace gentle for first-timers, the middle mode feels like a relaxed cruise, and the fastest gives pre-teens that lovely "I'm actually going somewhere" sensation. It will cope with the sort of mild neighbourhood inclines you'd roll a push scooter up without too much complaint. Load it up with a heavier early-teen near the top of its weight limit, and hills become more of a "persuade with kicks" scenario, but on the flat it still holds speed reasonably well.

The JETSON Relay, with its modest little motor, is noticeably more conservative. On flat ground with a smaller child it builds speed steadily rather than eagerly. Kids still get that electric magic moment - the "it keeps going without me kicking!" grin - but if they've ever tried a more powerful kids' scooter, the Relay won't exactly blow their socks off. Add a few kilos of rider weight or the slightest gradient and it quickly turns into a power-assisted kick scooter. Going downhill is great, of course. Coming back up, less so.

Throttle tuning also tells a story. The S4's response is pleasantly progressive: press a bit, get a bit; press more, get more. That predictability really helps nervous riders learn modulation and makes quick micro-adjustments in tight spaces easier. The Relay's throttle is closer to a glorified on/off switch linked to whichever speed mode you're in. It's simple and safe, but it doesn't reward finesse - which may be fine for beginners, but slightly wastes the three-mode concept once kids gain confidence.

Braking performance is roughly comparable in basic layout - e-brake plus rear fender - but the S4 again feels slightly more grown-up. Its electronic brake bites more decisively without being grabby, and the scooter's extra mass helps it settle rather than pitch. The Relay's e-brake is gentle, which is comforting for small kids but stretches stopping distances. You'll often see young riders revert to the rear stomp brake when things get interesting.

In everyday use, the S4 feels like an electric scooter that happens to be sized for kids. The Relay feels more like a toy where the motor is there to help, not to really drive.

Battery & Range

On spec sheets, both scooters promise short-to-medium play sessions rather than all-day adventures. In the real world, the ISINWHEEL S4 simply holds up a bit better.

With a light child cruising in the lower modes on flat paths, the S4 can stretch a family park outing without triggering "are we nearly out of juice?" anxiety. Start using the fastest mode all the time, put a heavier kid on board, or throw in some hills, and the range drops noticeably - but you still get a respectable chunk of continuous fun before the speed tapers off. When the battery is tired, the S4 rolls well enough to be kicked home without drama.

The Jetson Relay's tiny battery, by contrast, is very sensitive to those real-world factors. With a small rider and perfect conditions you can flirt with the advertised range. Add a few extra kilos, some cooler weather or a bit of wind, and you hit "low battery" surprisingly fast. Under load, the battery gauge has a habit of plummeting like a stone then bouncing back at rest - classic small-pack behaviour. Parents quickly learn to treat it as a rough suggestion, not gospel.

Charging is not exactly rapid on either scooter. You're looking at several hours from flat to full in both cases, effectively turning them into "once or twice a day" toys unless you schedule charging carefully. Given the Relay's much smaller battery, its glacial charge speed feels particularly stingy; there is no quick top-up before the afternoon ride if someone forgets to plug it in at lunch.

Range anxiety is therefore much more of a Jetson thing. With the S4 you plan for an afternoon; with the Relay you plan for a session.

Portability & Practicality

This is where the Jetson Relay fights back hard. It is properly, hilariously light. A reasonably coordinated eight-year-old can fold it and carry it up a flight of stairs without turning purple. In a packed car boot, several Relays can play Tetris around luggage where a single adult scooter would already be grumbling. Folded, it's short, slim, and easy to stash under a bed or behind a door.

The S4 is still very portable - much lighter than any adult scooter - but you feel the extra weight and bulk when you have to carry it one-handed for a while. For parents doing the classic "carry child's scooter plus your own shopping" juggle, the Relay is noticeably kinder to shoulders.

Folding mechanisms on both are simple and quick enough to trust a slightly supervised child with them. The S4's latch has a more substantial feel, clicking into place with more conviction. The Relay's system is straightforward and fast but aligns more with the rest of the scooter: functional, not exactly confidence-inspiring if abused daily.

In terms of living with them, both are low-maintenance: solid tyres mean no punctures, external cleaning is just a wipe-down, and there are no apps or firmware foibles to worry about. The big practicality caveat for the Jetson is storage behaviour: leave it uncharged in a cold garage all winter and there's a non-trivial risk the tiny battery won't wake up in spring. The S4's pack seems more tolerant, though good charging habits matter on both.

So: if your main requirement is "my kid must be able to carry it without involving my spine", the Relay wins. If you want something still portable but a bit sturdier and more versatile when actually rolling, the S4 is easier to live with.

Safety

Both scooters do a commendable job of ticking the "parent can sleep at night" boxes, but they reach slightly different levels of thoroughness.

Kick-to-start is standard on both, which is non-negotiable for kids: no accidental full-throttle launches from standstill when someone leans on the thumb trigger while gossiping. Both pair an electronic brake with a classic rear fender stopper, making the learning curve gentler for kids coming from manual scooters.

The ISINWHEEL S4, however, layers more seriousness on top. Its stronger electronic brake provides firmer, more controllable stopping, and the overall chassis stability at its top speed inspires more confidence when a child has to brake while turning or dodging a dog walker. The lighting package is also in a different league: bright headlight plus vivid deck lighting make the scooter impossible to miss during dusky evening rides, and parents actually like being able to spot their child from 200 metres away in a park.

The Jetson Relay includes a headlight, which is honestly more than some competitors at this price manage, but that's largely where the story ends. Visibility is decent from the front, less so from the sides and rear. Grip on the deck is acceptable, though slightly less generous than the S4's rubberised platform. Stability at its lower top speed remains fine as long as the surface is smooth; the small wheels and light frame just mean mishaps over debris are more likely to become dramatic wobbles.

On the electrical side, the S4's adherence to more stringent safety certifications is reassuring when you're charging it indoors. With the Relay you're mostly trusting Jetson's mass-market processes; not a disaster, but not particularly confidence-inducing either given the number of reports about early battery or charger failures.

In safety terms, both are broadly acceptable for supervised young riders. The S4, though, feels like it was designed by people thinking about safety first and toys second. The Relay feels designed the other way round.

Community Feedback

Price & Value

On sticker price alone, these two are close enough that discounts and local availability will decide the exact gap. The question is what you actually get for those euros.

The ISINWHEEL S4 delivers a broader feature set - lighting, display, music, stronger motor - and feels closer to an entry-level "vehicle" than a toy. Kids don't outgrow it quite as quickly, both in size and in excitement. From a value perspective, that translates into more seasons of enthusiastic use and fewer conversations about "upgrading" after only one summer.

The Jetson Relay looks tempting when it's on sale, especially stacked beside expensive adult scooters. The problem is that you are buying into very modest performance and a battery that many owners report as the first weak link. For a strictly flat neighbourhood and a small child, it can still be a reasonable deal - but as soon as expectations creep beyond that, its value proposition wears thin.

If you can stretch to the S4, the extra outlay feels justified in daily use. The Relay makes sense only if your budget is firm and your use case narrow.

Service & Parts Availability

ISINWHEEL operates much more like a pure micromobility brand, and it shows when things go wrong. Community reports of S4 issues - usually minor items like fenders or lights - are generally followed by quick responses, replacement parts, and helpful troubleshooting. Parts availability isn't on the level of the big commuter brands, but for this price class it's refreshingly competent.

Jetson, as a mass-market brand present in big-box retailers, offers a different kind of support experience. Officially, there's a warranty and support channels. In practice, owner reports are mixed: some get swift replacements, others get bounced between retailer and manufacturer, or offered modest discounts on new units instead of straightforward repairs. Spare parts outside the basic charger are not exactly easy to source in Europe, and most repairs beyond simple DIY tinkering quickly become uneconomical.

For European buyers especially, the S4 sits on much firmer ground in terms of long-term support. With the Relay, you are effectively accepting that if the battery dies inconveniently early, replacement might be more hassle than the scooter is worth.

Pros & Cons Summary

Parameters Comparison

Final Verdict - Which Should You Choose?

If you want the simple, honest answer: for most families, the ISINWHEEL S4 is the better buy. It rides more like a real scooter, has punchier performance that doesn't evaporate the moment you see a hill, and gives kids that coveted "grown-up" feel with its cockpit, lights and overall solidity. It also inspires more confidence at speed and seems to enjoy better long-term support, which matters when you're the one being asked to "fix it, please".

The JETSON Relay has a narrow but valid niche. If your child is younger or very light, your area is pancake-flat, and ultra-low weight plus tiny folded size are absolute priorities, the Relay can still be a fun entry point - provided expectations stay realistic about hills and battery longevity. It's easy to carry, easy to store and unintimidating to ride; just don't expect it to grow much with the rider.

Between the two, the S4 feels like a small step towards the real micromobility world, while the Relay feels like an electric stepping stone that your child will outgrow fairly quickly. If your budget allows, the S4 is the scooter that's more likely to keep your young rider smiling a bit longer and asking for "one more lap" rather than "a faster one next year".

Numbers Freaks Corner

These metrics strip away the marketing and look purely at what you get per euro, per kilogram and per watt-hour. Lower cost per Wh and per kilometre show how efficiently each scooter converts money into usable battery and range. Weight-related metrics highlight how much scooter you carry around for the performance and range you get. Efficiency (Wh/km) shows how gently each scooter sips its battery. Power-to-speed and weight-to-power ratios reveal how strong and lively a scooter feels for its size, while average charging speed tells you how long it must stay tethered to the wall relative to its battery size.

Author's Category Battle

Overall Winner Declaration

In the Numbers Freaks Corner, the ISINWHEEL S4 scores 10 points against the JETSON Relay's 0. In the Author's Category Battle, the ISINWHEEL S4 gets 33 ✅ versus 4 ✅ for JETSON Relay.

Totals: ISINWHEEL S4 scores 43, JETSON Relay scores 4.

Based on the scoring, the ISINWHEEL S4 is our overall winner. Between these two, the ISINWHEEL S4 simply feels like the more complete companion for a young rider - it rides with more confidence, offers a richer experience, and feels less like something they'll abandon after one summer. The JETSON Relay has its charm as a super-light, simple starter toy, but its limitations show up quickly once kids start exploring further or grow a little heavier. If you want your child's first e-scooter to feel like a proper little machine rather than a disposable gadget, the S4 is the one that will keep both of you happier, for longer.

That's our verdict when we try to stay objective – but hey, riding is mostly about emotions anyway, so pick the one that will make you look forward to your commute every single day.