How Nuzzle Handles Your Relationship Data — And Why It's Built Differently

The question couples should ask every relationship app

Before you put your daily emotional state, your conflict history, your partner’s vulnerabilities, and your most private shared moments into an app — you should ask: who can read this, and what happens to it?

For most couples apps, the honest answer is: the company can read it (or at least access the metadata), it lives on their servers, and it may be used to train models, generate aggregate insights, or inform advertising. These aren’t accusations — they’re just what server-side storage typically means.

Nuzzle was built with a different answer in mind.

How data actually flows in Nuzzle

Your device is the source of truth. Nuzzle is offline-first, built on a local database (Isar) that lives entirely on your phone. Every check-in, every glow, every pebble, every message is written to your device first. The app works fully without a network connection. No screen blocks on availability. No “loading” state that fails when you’re on the subway.

Sync uses encrypted changesets — not content. When your partner’s changes need to reach you, Nuzzle uses a CRDT (conflict-free replicated data type) sync engine. What this means in practice: the system generates small structural delta packets — descriptions of what changed — rather than transmitting readable content. These changesets travel through Firebase (Google’s infrastructure) as the transport layer.

Nuzzle does not own or operate backend servers. We have no proprietary database that stores your relationship content. We use Firebase as a transport and auth layer — it’s Google’s infrastructure, not ours.

We can’t read your content — by design. The architecture is structured so that even if someone subpoenaed Nuzzle, there would be no relationship journals, no message content, no conflict notes to hand over. We don’t have it. We built it that way deliberately.

What we do see

Transparency matters. Here’s what we do have access to:

• Account information — your email or Google account identifier, used for authentication via Firebase Auth
• Pairing metadata — a world ID that links two accounts; no content attached
• Sync changesets — structural deltas confirming that a sync event occurred; not readable content
• Aggregate crash and error logs — anonymised technical telemetry for debugging

That’s it. We see that your account exists and that sync is working. We don’t see what you said, how you felt, what you fought about, or what you’ve been building together.

No data harvesting — ever

A specific commitment, not a policy bullet point:

No analytics on your conversations. We don’t process message content, conflict notes, or journal entries for any purpose.

No AI training on your relationship. Your data is not used to train models — ours or anyone else’s.

No selling of anonymised insights. We don’t aggregate relationship data and sell it to researchers, advertisers, or third parties in any form.

No behavioural profiling. We don’t build advertising profiles from your usage patterns.

This commitment is reflected in the architecture, not just in a privacy policy. The reason we can make these commitments is that we don’t have the data in the first place.

What happens to your data if you cancel

Your on-device database persists on your phone unless you uninstall the app or manually delete the app data. The sync history in Firebase — the structural changesets — will be deleted per our standard data retention schedule.

There is no relationship history stored on Nuzzle’s servers to delete, because there isn’t a Nuzzle server that stores it.

If you cancel Premium, you lose access to cosmetics and seasonal drops. Your creature, your Nest, your timeline, your pebbles, your rituals — all of it stays. The relationship record you’ve built doesn’t belong to the subscription tier. It belongs to you.

Why this matters for intimate data specifically

Most people are reasonably comfortable with their email provider seeing email metadata, or their map app knowing where they’ve been. The stakes for relationship data are different.

What you share in a couples app includes: your emotional state on the worst days of your life, your partner’s fears and vulnerabilities, things said during conflict that you’d never want a stranger to read, the texture of your most private connection. This is uniquely sensitive data. It deserves a uniquely careful architecture.

Nuzzle was built by people who wanted to use a product like this and couldn’t find one they trusted. The privacy architecture is the product of asking: what would we want, as users, if we were going to put our relationship into an app?

The answer was: we’d want the app to be as blind as possible to the content, and as durable as possible with the record.

That’s what we built.