Mammaling

Cookies and storage

Last updated: 7 September 2026

In three lines. Mammaling carries no advertising and does not follow you around the internet: there are no ad cookies, no analytics cookies, no social media cookies. What it does store on your device is what the app needs to work — keeping you signed in, remembering your language, not losing a half-finished record, and working where there is no signal. And there is one single third-party exception: when you press play on a video in a species page, that video is served by YouTube.

This page lists, one by one, everything Mammaling writes to your phone or your computer. It is deliberately more detailed than the law requires: it is easier to trust something you can check.

  1. What a cookie is, and why this page says "storage"
  2. Everything Mammaling stores on your device
  3. Third parties: the video on species pages
  4. What there isn't
  5. How to delete it, and what you lose if you do
  6. If there were ever advertising
  7. Why we don't ask your permission for this
  8. Changes to this page
  9. Contact

1. What a cookie is, and why this page says "storage"

A cookie is a small text file a website leaves in your browser so it can recognise you next time. It's the word everybody knows, which is why it's in the title of this page — but for Mammaling it is the wrong word: Mammaling sets no cookies of its own.

It uses three other technologies that do something similar, and that the law treats the same way:

None of this is shared with anyone. It lives on your device and it is read by your device.

2. Everything Mammaling stores on your device

Necessary for the app to work

NameWhereWhat forHow long
therion-auth localStorage Keeps you signed in, so you don't have to type your password every time you open the app. Written by Supabase, who handle accounts for us. Until you sign out
mammaling_ui localStorage Your app preferences: interface language, the language you want species names in, whether you want scientific names, which sections you leave open, whether you've already seen the welcome. Until you delete it
mammaling_vista localStorage Whether you've chosen the mobile or the desktop layout by hand, instead of letting the app decide from your screen size. Until you delete it
mammaling (database) IndexedDB Your drafts and their photos. If you start a record in the field and run out of battery or signal, this is what stops you losing it. It empties once the record is uploaded. Until the record uploads
mammaling-v…, mammaling-app Cache Storage The app itself — its code and icons — stored so it opens quickly, and so it opens at all with no internet. Refreshed on each update
mammaling-paquete Cache Storage The field pack: species pages and their photos, downloaded on purpose by you so you can consult them where there's no signal. It's the largest thing here, and you control it from the app. Until you delete it in the app
mammaling-diario Cache Storage Your own observations, so you can see them offline. Until you delete it
therion_photocache localStorage An index of photo thumbnails you've already seen, so they aren't downloaded twice on your data plan. Refreshed as you go
mm_envoltorio, mammaling_recargado, mammaling_rescate sessionStorage Technical markers for recovering from an update that went wrong, without the page reloading in a loop. Until you close the tab
mambio_last_error localStorage The last error the app hit, so the repair screen can tell you what happened. It doesn't leave your device unless you send it. Overwritten

Only if we ever ask you

NameWhereWhat forHow long
mambio_consent localStorage Your decision about advertising and measurement, if there ever is any. Today this is never written, because there is no advertising and you are asked nothing. It exists so that once you have decided, you aren't asked again. Until you change it

3. Third parties: the video on species pages

Some species pages have a video. Those videos are served from YouTube, on its youtube-nocookie.com domain, which is the version Google offers for exactly this purpose: it writes no advertising cookies while the video sits there unplayed. But it is a Google service, and two things have to be said plainly:

What Google does with that data is governed by its own privacy policy, which is not ours to control.

Maps are a similar case, but a cleaner one: map tiles are served by MapTiler, CARTO and OpenStreetMap, and to draw your map they see your IP address and the area you are looking at. They write nothing to your device and they don't identify you.

4. What there isn't

This list matters as much as the previous one:

5. How to delete it, and what you lose if you do

From the app you control what takes up room: the field pack downloads and deletes whenever you want, and in Settings you can sign out, which clears your stored session.

From your browser you can clear it all at once: find the site settings for mammaling.org and choose "clear site data". On a phone, if you installed Mammaling as an app, uninstalling it clears everything.

Before you clear it, know this. Clearing the site's storage also removes two things you may not want to lose: any drafts you haven't uploaded yet — photos included — and the field pack, which you'll have to download again and which can be large. Observations you've already uploaded are safe: they live in your account, not on the device.

6. If there were ever advertising

There is none today, and the privacy policy says it isn't planned. But the app is already built inside for that case, and it's only fair to explain what would happen, because the answer is the opposite of the usual one:

Because the law doesn't require it for what exists today, and asking permission for something you can't refuse would be theatre. The European cookie rules (Article 5(3) of Directive 2002/58/EC, and in Spain Article 22.2 of the LSSI) exempt storage that is strictly necessary to provide the service you asked for. Keeping you signed in, remembering your language, not losing a half-finished record, and holding the pack you asked to download is exactly that.

The YouTube video is the one case that goes beyond necessary, and there your consent is you pressing play: until then, nothing from Google is loaded onto your device.

The day there is something that is not necessary — advertising, analytics, anything — you'll be asked first. That's what section 6 is about.

8. Changes to this page

If we change anything significant we'll say so inside the app and update the date at the top. If the change means adding storage that isn't necessary, it won't be switched on until you've decided.

9. Contact

If something on this page doesn't add up, or you want to know exactly what is stored on your device, write to [email protected] and we'll explain it.