# One photo, five secondhand platforms: FillSell slowly climbs amid France's resale-tool brawl · Chrome extension

> Source: https://stringers.io/en/ext/chrome_ooeagobimgoabciggfamljdfpkginhnm.html (Stringers / 什么值得做, generated 2026-11-08)
> Stringers answers one question every day: what small product can one or two people build in a few months and actually make money from. Numbers come from 15 databases we collect daily, each with source and date.
> For agents: these verdicts and the underlying databases (verified revenue, App Store / Google Play charts, ad libraries, GitHub, Product Hunt…) are queryable live over MCP — tools today / hot / products / directions / direction / data. Setup: https://github.com/komako-workshop/stringers (the user logs in at stringers.io → "配置 agent" to get a personal URL). Site index: https://stringers.io/llms.txt

> It hasn't really taken off yet: French resellers do need to list across platforms and fear selling one item twice, and US tools have either exited or don't serve France. It's growing slowly to a few hundred users through its own TikTok videos and a full set of comparison pages.

[Chrome extension](https://stringers.io/en/ext/index.md) · written 11-6

FillSell — Cross-post · fillsell.app

# One photo, five secondhand platforms: FillSell slowly climbs amid France's resale-tool brawl

**What it is** A tool for secondhand resellers: snap a photo, AI writes the title and price, and it posts to five French secondhand platforms at once, automatically delisting the others when one sells.

**Why it's taking off** It hasn't really taken off yet: French resellers do need multi-platform listing and fear double-selling, US tools have exited or don't serve France, and FillSell has grown to a few hundred users through its own TikTok talking-head videos and a set of comparison pages.

**B** **How you could follow** Don't build another one in France. Carry the same playbook to open countries, like Germany (Vinted + Kleinanzeigen) or Spain (Vinted + Wallapop). First get cross-posting and auto-delisting solid between two platforms, then acquire users with short videos about bans and making money.

Grade B: real demand, a clear monthly model priced on AI usage, and few similar extensions in Germany and Spain yet. But France is already crowded, FillSell hasn't proven it can scale, and the whole category faces the risk of Vinted tightening its anti-bot enforcement. Few people know about it yet

448 users · rating 5.0 (2)

A Frenchman alone in the southern suburbs of Paris built FillSell. Snap a photo on your phone, and AI writes the title, description, and price. A Chrome extension on your computer then posts the same item to Vinted, Leboncoin, eBay, Beebs, and Depop for you, and when one sells, the others are automatically delisted. The demand is real, and the big US players are absent from France, but it has only 448 extension users so far, and more than a dozen companies already crowd the same track. Below: what it does, where its users come from, who's competing, and whether there's room in another country.

### A video: "Vinted may ban you"

In 2026 Aug 10, the TikTok account @fillsell.app posted a talking-head video captioned: "Vinted may ban you, but your business doesn't have to stop. Sync + auto-repost, with FillSell." By 11-06, it had 35,111 views, 455 likes, and 52 comments, the most-viewed of the account's 71 videos.

The comments almost all ask the same thing: "What if my account gets banned?" "Can it still be used after a Vinted ban?" "We already get banned all the time..." Others asked "What are Clemz and FillSell?" (Clemz is France's oldest Vinted automation extension). From the comments, the video also showed a "3,400 € revenue" figure (inferred), and someone replied "3,400 is a good start."

These comments define the whole category: professional and semi-professional resellers in France sell on Vinted while also listing on Leboncoin and eBay. Their two biggest fears are the same item selling on two platforms at once, and being banned by the platform as a bot.

### What it actually is

FillSell's main product is a mobile app (on the iOS 2026-04-27 store under the French name "FillSell – Achat Revente / Reseller App"; Android package name app.fillsell.app) and the website fillsell.app. The Chrome extension was only listed 2026-07-25 and does one thing: in your own computer and your own logged-in browser, it clicks "publish" for you.

The division of labor works like this:

- **On the phone** : snap a photo → its "Lens" feature writes the title and description and suggests a price based on comparable listings → review it on the phone.

- **On the computer** : the extension uses your already-logged-in Vinted, Leboncoin, and Beebs accounts to post listings at a human pace, without touching your password. eBay uses the official API, so it can post even when your computer is off.

- **After a sale** : sold on one platform → automatically delisted from the others; unsold items are reposted on a schedule to move up in the listings.

It updates frequently: the Chrome store shows version 0.6.175, updated 11-05; the website screenshot still shows 0.6.105, meaning about seventy versions shipped in a few months. The iOS app is at version 2.8 (9-24). The developer registered in the store is a sole-proprietor business owner, Nicolas Svobodny, based in Saulx-les-Chartreux, Essonne; French business registries list this sole proprietorship's activity as SaaS software development. No funding found.

### How many people use it

Not many.

| Channel | Metric | Sources |
|---|---|---|
| Chrome Extension | 448 users, 5.0 rating, 2 ratings | Chrome Web Store, 11-01 |
| iOS (France store) | 3 ratings, 5.0 rating | App Store,11-06 |
| Android | Install count unverified | — |
| TikTok @fillsell.app | 883 followers, 71 videos, 6,043 total likes | TikTok,11-06 |
| Instagram @fillsell.app | 272 followers, 46 posts | Instagram,11-06 |

A third-party extension stats site has a curve: about 175 users in early September, about 490 in early November, adding over a hundred a month. The curve is unverified, but its scale matches the Chrome store's 448. Extension user counts likely understate its real size, since some people only use the mobile app plus eBay and never install the extension, but even if you multiply by several, it's a product with a few hundred to a thousand or two users.

### Where the money comes from

The money isn't in the extension; it's in in-app purchases and Stripe subscriptions on the website (fillsell.app/tarifs, updated 10-10):

| Tier | Monthly fee | AI-written listings per month | Reposts per month |
|---|---|---|---|
| Free | 0 € | 5 reviews | 50 times |
| Premium | 12.99 € | 40 reviews | 1,500 times |
| Pro | 29.99 € | 120 reviews | 5,000 times |
| Business | 59.99 € | 300 reviews | Any |

No annual plan and no free trial. The most notable part is what they charge for: **cross-platform posting, inventory sync, and auto-delisting on sale are all free** . Paid tiers only meter how many listings the AI writes for you, so one written listing posted to five platforms counts as one. Rival Klork charges 35 €/month for its Business tier with auto-delisting, and US-based Crosslist charges $39.99 for its Gold tier.

On TikTok, it has promoted a first-month 5% discount code FILLSELL50 (ended late October). How many paying users it has and how much revenue it makes isn't visible from outside.

### Where users come from

Almost all of its promotion is self-made. No media coverage found, and no one on X or Reddit has mentioned it in 90 days.

**Its own short videos.** TikTok and Instagram carry the same batch of talking-head videos with titles resellers want to hear: "Vinted may ban you," "URSSAF (the French social security agency) keeps asking for more... I found a way to take back control," "Since using FillSell, my profit tripled." The two most-viewed are 8-10's 35,111 views and 9-03's 11,216 views. One of 10-11's has 27,897 views but only 13 likes, an abnormal view-to-like ratio that most likely means paid promotion (inferred).

**A full set of comparison pages.** The website has 56 pages in total: 14 "FillSell vs X" pages (Clemz, Crosslist, DressKare, FlowDino, FLUF Connect, Klork...), 7 combination pages for "posting to A and B at once," and 3 "alternatives to X" pages. The centerpiece is a "2026 cross-platform listing tool comparison" that scores 15 tools line by line based on public pages, ranks FillSell first with 88 points and FLUF Connect second with 83, and states that "FillSell is our product." 11-06 Searching "post to Vinted and Leboncoin at the same time" in French, its Instagram Reel shows up on the first page.

**Catching traffic from the big players' exit.** US leader Crosslist announced on its official blog that it would stop onboarding new Vinted users starting 2026-10-02; List Perfectly and Vendoo never served France. FillSell immediately published a page titled "FillSell or Crosslist."

**Store keywords.** The iOS name packs in "Achat Revente / Reseller App", the Chrome name packs in "Cross-post". Doesn't seem to be working.

### Who it's competing with

The French market splits into two layers. Below are the Vinted-only automation extensions, each already sitting at a few thousand to ten thousand users. Above is "full French platform coverage, cross-posting", which only started piling up in 2026, and nobody has broken out yet. User counts are the Chrome Web Store numbers 11-01 to 11-07:

| Product | Launched | Users / review count | compared with FillSell |
|---|---|---|---|
| Clemz | 2021-06 | 10,000 / 154 | Vinted-only re-listing and auto-follow, no cross-platform |
| Dotb | 2024-05 | 10,000 / 95 | Vinted closet automation, no cross-platform |
| Bleam | 2025-10 | 7,000 / 31 | Vinted automation + AI assistant |
| Vintex | 2024-11 | 7,000 / 80 | Vinted seller helper |
| Redrip | 2026-04 | 2,000 / 39 | Vinted-first, with cross-platform |
| FLUF Connect | 2025-05 | 1,000 / 10 | UK-born, more European platforms, weaker French platform coverage than FillSell |
| Klork | 2026-07-11 | 715 / 3 | Launched almost the same month, same product, +63 users in a week |
| StoFlow | 2026-02 | 212 / 6 | Publishes from a server, runs even with your computer off |
| Crosslist / Vendoo / List Perfectly | Years | US leader | Mostly US platforms, doesn't serve or has exited French Vinted |

Klork and FillSell launched two weeks apart, selling the same line: "publish your Vinted closet everywhere." FillSell's differences are real: the widest platform list (it claims to be the only one posting to all five platforms, and almost nobody covers Beebs, the baby/kids secondhand platform), phone photo as the entry point, and auto-delisting on the free tier. But these are all feature lists, and rivals can add them in a few weeks.

Hanging over everyone is one problem: Vinted offers no cross-platform posting, keeps tightening its detection of automation, and Crosslist's blog has written about account bans lasting 24 hours. If Vinted tightens again, this whole layer of tools has to be rebuilt.

### Another country, still empty?

FillSell hasn't taken off, but it shows something: European secondhand platforms are strongly localized, and every country pairs "Vinted + a local classifieds veteran." US tools ignore all of it. The French pairing is already crowded, and other countries have far fewer similar extensions (Chrome Web Store, as of November):

- **Germany (Vinted + Kleinanzeigen)** : the largest Kleinanzeigen extension, "Kleinanzeigen Manager – AI Powered", has 558 users but handles only one platform; "Kleinanzeigen Boost" has 26 users. I haven't seen anyone pairing Vinted with Kleinanzeigen.

- **Spain (Vinted + Wallapop + Milanuncios)** : "Wallapop, Milanuncios y Facebook" has 380 users; Spain's Ruit has 507 users and pairs Vinted with eBay.

- **Netherlands (Vinted + Marktplaats)** : the Marktplaats extension with ten thousand users blocks ads for buyers. It doesn't help sellers post.

- **Italy (Vinted + Subito)** : nothing found.

These are only extensions, so pure web or pure app tools may exist that I didn't see. But at least on the Chrome Web Store, the "two major platforms cross-posting" slot in Germany and Spain is empty.

### If it were you

**B.** The demand is real and the revenue model is clear, but France is saturated, and the whole category lives under Vinted's enforcement risk. FillSell itself hasn't shown this business can scale, so copying it means betting on a product that hasn't proven itself. What's worth doing is carrying its playbook into a country that's still open.

- **Who it suits** : 1–2 people who are native to or live in Germany, Spain, Italy, or the Netherlands, have sold on Vinted and a local platform, know what a ban feels like, can write browser extensions, and are willing to keep fixing things every time the platforms change.

- **Who it doesn't suit** : anyone who wants another one in France (Clemz and Dotb sit below with ten thousand users, Klork, FillSell, Redrip, and StoFlow sit above); anyone who can't stomach "the platform changes and everything stops"; anyone who wants server-side account hosting or bulk account rotation (the easiest to ban, and the hardest to get users to trust with passwords).

- **How to build it** : follow its division of labor. Phone photos, AI writes copy and pricing, and the extension publishes from the user's own browser at a human pace without touching passwords. Start with two platforms only (Germany: Vinted + Kleinanzeigen; Spain: Vinted + Wallapop), and make "sell in one place, auto-delist the other" rock solid, since that's the sharpest pain for resellers. Cross-posting and auto-delisting stay free, and the subscription charges by the number of AI-written listings. Price against its 12.99 / 29.99 €.

- **How to get users** : short-video voiceovers that lead with fear and money: "What if Vinted bans your account, what happens to your business?", "What if the same item sells twice?", "How much revenue did I make this month?" Its most-viewed video is about a ban. Then copy its approach with comparison pages and "platform A + platform B at once" pages, written in the local language, to capture long-tail search. Whenever a major tool exits a platform, publish an "alternative to X" page that same week.

- **Launch window** : go live before the spring declutter season in 2027 (3–April), when secondhand listings peak each year (inference).

- **What would prove the call wrong** : ① Vinted launches official multi-platform sync, or bans all automation extensions at scale. ② Six months on, FillSell and Klork are still stuck under a few thousand users, which would mean even France, the most mature market, can't sustain cross-platform tools, and a new country would be smaller still. ③ FillSell or Klork launches German or Spanish versions first and starts spending on TikTok.

### Data and sources

Chrome Web Store listing (FillSell version and update date 11-06; each extension's users and rating 11-01 to 11-07); App Store France storefront (11-06); fillsell.app pricing page (updated 10-10), official comparison pages and sitemap (11-06); TikTok @fillsell.app profile, videos, and comments (11-06); Instagram @fillsell.app (11-06); Crosslist official blog on Vinted; French company registry societe.com. User growth curves come from third-party stats sites and are unverified; anything marked "inference" is inference.

[Chrome store page ↗](https://chromewebstore.google.com/detail/fillsell-%E2%80%94-cross-post/ooeagobimgoabciggfamljdfpkginhnm)

**Research notes: competitor table, acquisition evidence, full research report**

Competitors

| Name | Where | Launched | Scale | How it differs from this one |
|---|---|---|---|---|
| Clemz | Chrome | 2021-06 | 10,000 users / 154 reviews | Vinted-only single-platform automation, no cross-platform |
| Dotb | Chrome | 2024-05 | 10,000 users / 95 reviews | Vinted closet automation, no cross-platform |
| Bleam | Chrome | 2025-10 | 7,000 users / 31 reviews | Vinted re-listing + AI assistant, no cross-platform |
| Klork | Chrome | 2026-07-11 | 715 users, +63 in a week | Direct rival from the same period; auto-delisting needs the €35/month Business tier and covers only Depop beyond the core platforms |
| FLUF Connect | Chrome | 2025-05 | 1,000 users / 10 reviews | UK-born, more European platforms, French Leboncoin/Beebs coverage weaker than FillSell |
| StoFlow | Chrome | 2026-02 | 212 users / 6 reviews | Server-side publishing, runs with the computer off; no Beebs/Depop |
| Redrip (Vinted Assistant) | Chrome | 2026-04 | 2,000 users / 39 reviews | Vinted-first re-listing + cross-platform |
| Relistly | Web | Not verified | Not verified | Cross-platform for European Vinted, no phone AI photo entry point (per FillSell's comparison page) |
| Crosslist | Web | Years | Top US player, unverified | Closed Vinted to new users from 2026-10-02, doesn't serve EU residents |
| List Perfectly / Vendoo | Web | Years | Top US player, unverified | Serves only US platforms, doesn't cover Vinted France / Leboncoin / Beebs |

Where users come from

- **Verified** **own-account TikTok videos** : @fillsell.app has 883 followers and 71 posts; one video has 2026-08-10 35,111 views / 455 likes (TikHub 2026-11-06).

- Inferred **TikTok paid promotion** : 2026-10-11 one 27,897 views with only 13 likes, an unusually low like-to-view ratio, suggesting it was boosted; no record in the ad library

- **Verified** **Instagram Reels** : @fillsell.app has 272 followers and 46 posts, same batch of videos; a Reel appears on the homepage for the search "publier vinted et leboncoin en même temps"

- **Verified** **Programmatic SEO comparison pages** : sitemap has 56 pages, including 14 vs/comparison pages, 7 platform-combination pages, and 3 alternative pages; 15 self-rated first on a feature scorecard at 88

- **Verified** **Riding a platform event (Crosslist exits Vinted)** : Crosslist's blog announced it was closing Vinted to new users; FillSell published a "FillSell ou Crosslist" page

- Inference **Partnerships with French resale creators** : the recall mentioned this, but only official-account content turned up; no third-party creators found

## FillSell — Cross-post (Chrome extension ooeagobimgoabciggfamljdfpkginhnm)

### One line

A phone-first cross-posting tool for secondhand resale, built by French indie developer Nicolas Svobodny. The user takes one phone photo, and AI (Lens) writes the title, description, and suggested price. The Chrome extension then posts the same item to Vinted, Leboncoin, eBay, Beebs, and Depop (the Play description also lists Opla) inside the user's own browser, using their logged-in session. When an item sells, it's automatically delisted elsewhere, and listings are periodically "bumped" back up. The Chrome extension is only the executor; the real entry points are the iOS/Android apps and fillsell.app.

### Verdict

**It hasn't broken out yet.** As of 2026-11, the extension has 448 users and 2 ratings (chromestore library 2026-11-01); the iOS France store has 3 ratings (iTunes lookup, 2026-11-06); the official TikTok account has 883 followers. It's an early product in the crowded French Vinted tools category, positioned on "the widest platform coverage, with cross-posting and auto-delisting in the free tier." Growth comes mainly from its own TikTok and Instagram videos plus a full set of SEO comparison pages. The timing is notable: Crosslist (a US leader) closed Vinted to new users from 2026-10-02, and US giants List Perfectly and Vendoo don't serve France, so the French "multi-platform cross-posting" gap really does exist. But Klork, StoFlow, FLUF Connect, Relistly, Redrip, and others are all going after the same space.

### Data

- Chrome: 448 users, 5.0 stars / 2 reviews (chromestore library item_snap 2026-11-01, a single snapshot, so weekly growth can't be calculated). Version 0.6.175,2026-11-05 updated (store listing, fetched via Jina 2026-11-06); the official site screenshots still show 0.6.105, meaning releases are very frequent. Listed 2026-07-25.

- The recall cited the extops curve: 9/1 about 175 → 11/6 about 492 (30 days, +153). **Unverified** (extops / chrome-stats pages returned no data this time).

- iOS: "FillSell – Achat Revente / Reseller App", id 6762152785,2026-04-27, version 2.8 (2026-09-24), France store 3 ratings, 5.0 stars, category Business (iTunes lookup 2026-11-06). The appstore library has no chart records for this app, so it hasn't appeared on any chart we track.

- Android: app.fillsell.app; not in the googleplay library; install count unverified.

- Pricing: free €0 (5 AI listings and 50 re-lists per month), Premium €12.99, Pro €29.99, Business €59.99/month; no annual plan, no trial; Stripe plus in-app purchases (https://fillsell.app/tarifs, updated 2026-10-10). Billed by number of listings (AI-written), not by platform.

- Entity: the Chrome Web Store lists the developer as EU trader "NICOLAS STANISLAS JACQUES SVOBODNY" in Saulx-les-Chartreux 91160; societe.com has a sole-proprietor company under that name (SIREN 928578434), registered for SaaS software development. Individual developer, no sign of funding.

### Competitors

Similar extensions found by full-text search of the chromestore library for "vinted" / "leboncoin" (user counts are 2026-11-01~07 snapshots):

| Product | Channel | Launched | Scale | How it differs from FillSell |
|---|---|---|---|---|
| Clemz | Chrome + App | 2021-06 | 10,000 users / 154 reviews | Vinted-only automation (re-listing, auto-follow), no cross-platform |
| Dotb | Chrome | 2024-05 | 10,000 / 95 | Vinted closet automation, no cross-platform |
| Bleam | Chrome | 2025-10 | 7,000 / 31 | Vinted automation + AI assistant, no cross-platform |
| Vintex | Chrome | 2024-11 | 7,000 / 80 | Vinted seller helper |
| Listelf (formerly Crosslist Magic) | Chrome | 2021-04 | 5,000 / 72 | UK/US-first cross-listing, not focused on French platforms |
| Redrip(Vinted Assistant) | Chrome | 2026-04 | 2,000 / 39 | Mainly Vinted-based reposting + cross-listing, no full coverage of Leboncoin/Beebs |
| VintHelper | Chrome | 2026-05 | 2,000 / 57 | Vinted bots |
| FLUF Connect | Chrome + App | 2025-05 | 1,000 / 10 (extension) | UK-born, more European platforms; FillSell's own comparison page scores it 83 points (FillSell 88) |
| Vindy | Chrome | 2024-07 | 1,000 / 27 | AI listings, model photos, pricing, Vinted only |
| Klork | Chrome | 2026-07-11 | 715 / 3, +63 in one week | A direct rival that launched around the same time, "push your Vinted closet everywhere"; auto-delisting needs the 35 €/month Business tier |
| Ruit | Chrome | 2025-05 | 507 / 19 | Spain, cross-listing across Vinted + eBay |
| StoFlow | Chrome + cloud | 2026-02 | 212 / 6 | Vinted/Leboncoin/eBay/Etsy/Vestiaire, runs server-side, still posts when your computer is off |
| Reposter | Web | — | Not verified | Leboncoin + Vinted auto-posting + automatic buyer message replies |
| Crosslist / Vendoo / List Perfectly | Web + extension + app | Years | Top US player (scale unverified) | Mainly US platforms; Crosslist stopped offering Vinted to new users from 2026-10-02 and doesn't accept EU residents (per FillSell's comparison page); List Perfectly and Vendoo don't serve France |
| Vinted official | Big-company features | — | — | No cross-listing offered; instead they're tightening detection of automation (Crosslist blog) |

Summary: many single-platform Vinted automation tools exist (thousands to ten thousand users); the 'full French-platform cross-posting' niche only got dense in the last 2026 years (Klork, StoFlow, Relistly, Redrip, FillSell), all at the few-hundred to two-thousand user level, with no clear leader.

### Growth tactics (evidence)

1. **Own TikTok account** (@fillsell.app, 883 followers, 71 videos, 6,043 total likes, TikHub 2026-11-06). Top two: 2026-08-10 "Vinted peut te bloquer…" with 35,111 views / 455 likes; 2026-09-03 with 11,216 views / 240 likes. Another 2026-10-11 has 27,897 views but only 13 likes, an abnormal views-to-likes ratio, **suspected paid promotion via Spark Ads (inference, unverified; our tiktokads library only covers European ads and this product isn't on the list)** . Content is talking-head style: "URSSAF wants you to pay more → control it with automation", "my profit tripled", the self-starring creator format.

2. **Instagram** (@fillsell.app, 272 followers, 46 posts, Jina search snippet), same Reels reused. The recall mentioned "several French resale creators promoting it"; only the official account's Reels were found, **creator partnerships unverified** .

3. **Programmatic SEO pages** : sitemap has 56 URLs in total, including 14 comparison pages (vs Clemz, Crosslist, DressKare, FlowDino, FLUF Connect, Klork…), 7 "platform A + platform B crosslisting" combo pages, 3 alternative pages, 8 blog posts, and an English version. The core piece is a "2026 crosslisting app comparison" scoring table, rating 15 tools line by line from public pages, with itself ranked first at 88 points, and a statement that "FillSell is our product". When searching "publier vinted et leboncoin en même temps", FillSell's Instagram Reel already appeared on the first results page (Jina search 2026-11-06).

4. **Store search** : the iOS name includes "Achat Revente / Reseller App", the Chrome name includes "Cross-post", keyword squatting. Effect unknown.

5. **Platform event** : Crosslist stopped offering Vinted to new users from 2026-10-02, and US tools generally don't serve the EU. FillSell wrote a dedicated "FillSell ou Crosslist" page to capture this search traffic.

6. Not found: Reddit / X / HN / Product Hunt discussion (x-radar 90 days 0 results), press coverage, Meta ads (no records in the metaads library, but that library only tracks listed products).

### Why it (hasn't) broken out

- The demand is real: France's secondhand market has three big pillars (Vinted, Leboncoin, eBay) plus Beebs for baby goods, and professional and semi-professional resellers naturally need multi-platform listings and protection against selling one item twice.

- Top US tools are absent in France: Crosslist shut off Vinted, and List Perfectly/Vendoo don't cover French platforms, leaving a gap for "French-native cross-listing".

- But the gap is crowded: Klork (launched the same month), StoFlow, Relistly, Redrip and FLUF are all building in it; single-platform Vinted automation tools (Clemz, Dotb, Bleam) already each have 7k–10k users.

- Platform risk looms overhead: Vinted is tightening automation detection and will ban accounts for 24 hours (Crosslist blog's own words), affecting every tool. FillSell hedges with "human-paced, in your own session, never touches your password".

- On scale: 448 extension users, 3 iOS ratings, paid conversion unknown. Even going by the extops curve in the recall, it's a slow climb of a hundred or two installs a month.

### Differentiation

1. **Coverage** : claims to be the only tool that posts to Vinted + Leboncoin + eBay + Beebs + Depop at once (per its comparison page 2026-10-09; self-reported, not independently verified). Beebs (second-hand baby goods) is barely served by anyone else.

2. **Phone-centric** : snap a photo → AI writes the listing and prices it against comparable active listings; review on your phone, the desktop extension executes; eBay goes through the official API, so it posts even with your computer off.

3. **Core features on the free tier** : cross-platform posting, syncing existing listings and auto-merging them into one card, and auto-delisting on sale are all free; paid plans only meter "how many AI listings were written". Rival Klork charges 35 €/month for auto-delisting, and Crosslist's Gold tier costs $39.99.

4. **Compliance pitch** : runs inside the user's own browser session at human pace and never stores passwords, hedging against fear of Vinted bans.

These differences are real, but right now they're **not enough to explain a breakout** , which hasn't happened yet. The differentiation is "the most complete feature list + the lowest price to enter", easy for similar tools to match; the real moat (stability against anti-detection, speed of platform adaptation) isn't visible from the outside.

### Visibility

**Few people know about it yet** : no public revenue, no press, no discussion on X/Reddit; spread only through its own TikTok/IG accounts. There's no herd to follow; it is itself one of a wave of copycats, and contemporaneous Klork (2026-07-11) is almost the same product.

### Takeaways

- Programmatic SEO comparison pages: score each of 15 same-niche tools one by one from public information, publish the scoring rules, declare your own identity, and open a page for every "A vs B" and "platform combo", cheaply grabbing long-tail "alternative / vs / two-platform cross-post" queries.

- Capture traffic around platform events: when a major tool exits a platform (Crosslist leaving Vinted), immediately publish an "X alternative" page.

- Free core features, meter by AI usage: remove the cross-listing barrier entirely and use the most expensive part, AI generation, as the billing unit.

- Split phone and browser extension: the phone handles content creation (photos/AI), the extension executes inside the user's session, sidestepping server-side risk controls and the trust problem of storing passwords.

### Uncertain

- The extension's real growth curve (only one snapshot; extops data unverified), Android install count, paid user count and revenue.

- Whether the TikTok video with high views and low engagement was ad-boosted, and whether there are creator partnerships.

- After Vinted tightens detection, its ban rate, and whether the "5-platform full coverage" can be sustained.

### Sources

- chromestore library item / item_snap / item_growth (2026-11-01~07)

- Chrome Web Store listing [chromewebstore.google.com/detail/ooeagobimgoabciggfamljdfpkg…](https://chromewebstore.google.com/detail/ooeagobimgoabciggfamljdfpkginhnm)

- Website [fillsell.app/](https://fillsell.app/), [fillsell.app/tarifs](https://fillsell.app/tarifs), [fillsell.app/comparatif/meilleures-applications-crosslisting](https://fillsell.app/comparatif/meilleures-applications-crosslisting), [fillsell.app/sitemap.xml](https://fillsell.app/sitemap.xml)

- iTunes lookup id=6762152785 (country=fr); Google Play app.fillsell.app description

- Crosslist blog [crosslist.com/blog/vinted-cross-listing](https://crosslist.com/blog/vinted-cross-listing)

- TikHub: @fillsell.app profile and posts (2026-11-06); Instagram @fillsell.app (Jina search snippet)

- societe.com sole-proprietor company page [www.societe.com/societe/monsieur-nicolas-svobodny-928578434.…](https://www.societe.com/societe/monsieur-nicolas-svobodny-928578434.html)

- x-radar search "fillsell" 90 days 0 results; metaads / tiktokads libraries: no records

This article was written by AI from public data and the data we collect daily. Numbers are sourced, and inferences are labeled.