Dating-app safety • Editorial review

Is 3Fun Safe? What the 2019 Breach Exposed

3Fun is a real, genuinely popular non-monogamy app with an unusually good free tier — and a documented 2019 breach that exposed users' precise location, photos, date of birth and private chats. 3Fun said it fixed the flaws; we can't independently confirm its security today. Usable if you go in eyes-open and share the bare minimum.

6 min read

If you've searched "is 3Fun safe," you've probably already found the headline: in 2019 a security firm called it among the worst it had seen in a dating app. That's real, and we won't bury it. But "safe" and "legit" aren't the same question, and the honest answer to each is different. 3Fun is a real product with a genuinely large niche userbase — and it also carries a documented security history that anyone considering it deserves to know up front. This piece is about that history: what leaked, what 3Fun said it did about it, what we can and can't confirm today, and who should still use it versus who should walk away. For the scored product verdict on our rubric, see our full 3Fun review and score.

Is 3Fun safe? The short answer

3Fun is legit — a real, operating app with millions of users and a working free tier. Whether it's safe depends on your risk tolerance, because the app holds unusually sensitive data (your location, your face and your explicit preferences) and it has a documented 2019 breach of exactly that data. 3Fun says it fixed the flaws. We can't independently verify its security today, so our honest position is: usable if you go in eyes-open and minimise what you share — not something we'd tell you is proven-secure.

What 3Fun is

Launched in 2015, 3Fun is an app-first dating product aimed at couples and singles exploring open, polyamorous or no-strings connections — threesomes most of all. It reports more than 10 million downloads, with the strongest concentration in North America and Europe. Couple and paired-profile accounts are a first-class option, not a workaround, which is what sets it apart from a mainstream app where two people share one profile awkwardly. The interface feels familiar to anyone who's used Tinder — a swipe deck, matches, chat — and its free tier actually lets you match and message, which is unusual in a category where the inbox is normally the paywall.

That combination — sensitive-by-design data plus mainstream popularity — is exactly why its security history matters more than it would for an ordinary app.

The 2019 breach, step by step

Here's the part most 3Fun write-ups skip, stated plainly and sourced.

• August 2019 — the finding. The UK security firm Pen Test Partners published research showing that 3Fun exposed users' real-time location, photos, date of birth and private chat data through the app's back-end (API), and that the researcher considered it among the worst security he'd seen in a dating app.
• The location flaw specifically. The most serious issue was location: the app returned users' precise coordinates through the API even when a user had set their location to hidden. In other words, the privacy control that was supposed to protect location didn't actually stop the data from being served.
• 3Fun's response. 3Fun stated at the time that it had fixed the vulnerabilities the researchers reported.

We have not independently re-tested the app's current security, so we treat this as a documented past finding with remediation we can't confirm — not a live breach today, but not a clean bill of health either. In a category where the app holds your location, your photos and your explicit preferences, that history matters. Every factual claim above is cited in Sources below; anything about the app's state right now is something we're flagging as unverified rather than asserting.

What data 3Fun holds on you

The reason the 2019 finding lands harder than a typical app leak is the kind of data involved. To work at all, a non-monogamy app like 3Fun collects and stores:

• Precise location — to show nearby matches, often accurate to a small radius.
• Face photos — your profile pictures, and any images you send inside a chat.
• Date of birth / age — collected at signup.
• Orientation and explicit preferences — the whole point of the profile is stating what you're into.
• Private messages and media — chats, pictures, audio and video shared in a match.

For a mainstream app, a leak of that data is bad. For an app whose entire premise is non-monogamy and threesomes, the same leak carries an added outing / exposure risk that can affect relationships, jobs or safety. That's not a reason to panic — it's a reason to treat the app as one you give the least data you can get away with, which is the practical takeaway of the whole 2019 episode.

Using 3Fun more safely

If you decide the trade-off is worth it, you can meaningfully lower your exposure without giving up the app:

• Sign up with a burner email and, if you can, a separate number — keep the account off your main identity.
• Limit identifying photos. Avoid pictures that also appear on your public social profiles (reverse-image search links them), and skip anything with your workplace, home or license plate in the frame.
• Turn off precise/background location in your phone's app settings, and don't rely on an in-app "hide location" toggle as real protection — the 2019 finding is a reminder that such toggles can fail.
• Don't treat the screenshot-block as security. 3Fun blocks in-app screenshots of profile photos, but that's a speed-bump, not a guarantee — assume anything you send can be captured.
• Watch for fake or recycled profiles. They're a recurring complaint in the niche; never send money, and video-chat before meeting.

None of this makes any app breach-proof. It just means that if something leaks, there's less of you in it.

Is 3Fun legit — or a scam?

Worth separating from the safety question: 3Fun is not a scam in the "fake app that takes your money and vanishes" sense. It's a real product from an established developer, with a large active userbase and an honest free tier — you can verify it's a working app before you ever pay. The paid subscription unlocks extras (instant matching, unlimited likes, messaging before matching, incognito mode), and the upsell prompts show up often, but the core experience is genuinely free. The legitimate criticisms are the privacy history above and the usual niche-app issues (thin outside big cities, some fake profiles) — not fraud.

Who should use it — and who should skip it

3Fun fits adults who already know they're looking for threesomes, swinging or non-monogamous connections, want an app where that's the default, and are comfortable managing the privacy trade-off by sharing the minimum. Couples who want to browse together get a first-class experience.

Skip it if a past leak of location/photo/chat data is a dealbreaker for you — that's a completely fair and honest reason to choose a different product — or if you need traditional one-to-one dating, or you're outside a dense metro where the pool thins out fast.

For the full breakdown — our 5-axis score, the safety grade and how it ranks against Feeld — read the complete 3Fun review.