Licences

Last updated: 25 October 2026

4D Ages is built with open-source software and open data. We're grateful to everyone who makes them. Here they are, with their licences.

Software

React, React Native, React Native Web (Meta and contributors), MIT licence.
Expo and its libraries (650 Industries and contributors), MIT licence.
React Navigation, React Native Screens, Reanimated, Safe Area Context, Pager View, Tab View, WebView, Slider, DateTimePicker, Async Storage (Software Mansion, the React Native community and contributors), MIT licence.
Google Sign-In for React Native (Vojtech Novak and contributors), MIT licence.
Supabase JavaScript client (Supabase), MIT licence.
Zustand (Poimandres), MIT licence. fflate (Arjun Barrett), MIT licence.
MapLibre GL JS (MapLibre contributors), BSD 3-Clause licence.
three.js (three.js authors), MIT licence, for the album on the home page (licence).
Material Design Icons (Pictogrammers), Apache License 2.0.

The MIT licence: Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files, to deal in the Software without restriction… The software is provided "as is", without warranty of any kind. The full texts of these licences are at opensource.org/licenses/MIT, opensource.org/licenses/BSD-3-Clause and apache.org/licenses/LICENSE-2.0.

Milestones and play ideas

Typical milestone ages are based on published developmental guidance, including the CDC's milestone checklists and the WHO Motor Development Study. The lines are written in our own words.
Play ideas use information from the CDC's “Learn the Signs. Act Early.” and from nhs.uk. Contains public sector information licensed under the Open Government Licence v3.0.

Photos

Some photos in the album on the home page are from Unsplash, under the Unsplash License: a baby holding a finger by Tembinkosi Sikupela, a mother holding her scans by Brooke Balentine, a baby’s place at the table by Carrie Allen, a birthday cake by Imants Kaziļuns, a golden retriever by Barnabas Davoti, a baby’s first steps by Sandra Seitamaa, and a toddler drawing by Erika Fletcher.
The illustrations in the home page album were made with an AI image tool for 4D Ages.

Fonts

Fraunces (Undercase Type), SIL Open Font License 1.1.
Heebo (Oded Ezer, The Heebo Project Authors), SIL Open Font License 1.1, for Hebrew on the website and the words in books (licence).
Fredoka (The Fredoka Project Authors), SIL Open Font License 1.1, for titles in books (licence).
Frank Ruhl Libre (The Frank Ruhl Libre Project Authors), SIL Open Font License 1.1, for titles in books (licence).
For album themes, each under the SIL Open Font License 1.1 with its authors' copyright in its licence: Bellefair (licence), Bree Serif (licence), Caveat (licence; also for the notes on the home page), Cormorant Garamond (licence), David Libre (licence), Gveret Levin (licence), Italiana (licence), Marcellus (licence), Patrick Hand (licence), Playfair Display (licence), Playpen Sans Hebrew (licence), Secular One (licence) and Suez One (licence).
For the book editor's font list, each under the SIL Open Font License 1.1 with its authors' copyright in its licence: Alef (licence), Amatic SC (licence), Assistant (licence), Karantina (licence), Rubik (licence), Varela Round (licence).
Chewy (Font Diner, Inc DBA Sideshow), Apache License 2.0, for album themes (licence).

Maps and places

Place search by Nominatim, using OpenStreetMap data.
The world map in books and videos is drawn from Natural Earth, in the public domain.

Music and pictures

The music in videos is from the FreePD collection (archive.org/details/freepd): "Shining Stars", "Ukulele Song", "Magic in the Garden" and "Celebration", all in the public domain (CC0).
The fruit and vegetable photos for the weeks of pregnancy are in the public domain or CC0, from Wikimedia Commons and other public collections.
The food photos in Foods & allergens are from Wikimedia Commons. These are in the public domain or CC0: Asparagus, Beans, Bread, Broccoli, Cashew, Celery, Couscous, Cream cheese, Honey, Kale, Lupin flour, Mustard, Oats (porridge), Olive oil, Potato, Rice, Salmon, Tuna. The rest are shared under Creative Commons licences and credited here (each one cropped to a square):
- Almond: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Apricot: photo by Benjamint444, CC BY-SA 3.0, cropped.
- Barley: photo by Glane23, CC BY-SA 3.0, cropped.
- Beef: photo by Michael C. Berch, aka MCB at en.wikipedia, CC BY-SA 2.5, cropped.
- Beetroot: photo by BriannaWalther, CC BY-SA 3.0, cropped.
- Brussels sprouts: photo by Eric Hunt, CC BY 2.5, cropped.
- Butter: photo by Jacek Halicki, CC BY-SA 4.0, cropped.
- Cheese: photo by J.P.Lon, CC BY-SA 3.0, cropped.
- Chicken: photo by Evan Swigart from Chicago, USA, CC BY 2.0, cropped.
- Chickpeas: photo by AlixSaz, CC BY-SA 4.0, cropped.
- Cinnamon: photo by Simon A. Eugster, CC BY-SA 3.0, cropped.
- Cottage cheese: photo by FASTILY (TALK), CC BY-SA 3.0, cropped.
- Courgette: photo by Willis Lam, CC BY-SA 2.0, cropped.
- Cows' milk in food: photo by Janine Chedid, CC BY-SA 3.0, cropped.
- Crab: photo by Hans Hillewaert, CC BY-SA 4.0, cropped.
- Cumin: photo by OttawaAC, CC BY-SA 3.0, cropped.
- Dried apricots: photo by Andrey Butko, CC BY-SA 3.0, cropped.
- Edamame: photo by Tammy Green (aka Zesmerelda) from Chicago Upscale Dining + Lounge Republic Pan-Asian Restaurant [1] in Ontario & Rus, CC BY-SA 2.0, cropped.
- Egg: photo by Ramesh NG, CC BY-SA 2.0, cropped.
- Fromage frais: photo by Kaouther Bedoui, CC BY-SA 4.0, cropped.
- Garlic: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Ginger: photo by HaJunkiyada, CC BY-SA 4.0, cropped.
- Grapes: photo by Vyacheslav Argenberg, CC BY 4.0, cropped.
- Green beans: photo by Undeka 11, CC BY-SA 4.0, cropped.
- Hazelnut: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Herbs (basil, parsley): photo by David J. Stang, CC BY-SA 4.0, cropped.
- Kiwi: photo by André Karwath aka Aka, CC BY-SA 2.5, cropped.
- Lamb: photo by Pavel Ševela, CC BY-SA 3.0, cropped.
- Millet: photo by Thamizhpparithi Maari, CC BY-SA 3.0, cropped.
- Mozzarella: photo by Greg O'Beirne, CC BY-SA 3.0, cropped.
- Mushroom: photo by chris_73, CC BY-SA 3.0, cropped.
- Mussels: photo by Rainer Zenz, CC BY-SA 3.0, cropped.
- Onion: photo by Colin, CC BY-SA 3.0, cropped.
- Orange: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Parsnip: photo by Takeaway, CC BY-SA 3.0, cropped.
- Pasta: photo by David Adam Kess, CC BY-SA 4.0, cropped.
- Peanut: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Peas: photo by David Adam Kess, CC BY-SA 4.0, cropped.
- Pistachio: photo by THOR, CC BY 2.0, cropped.
- Plum: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Polenta (corn): photo by it:User:Dorothy61n1, CC BY-SA 3.0, cropped.
- Pork: photo by Rainer Zenz, CC BY-SA 3.0, cropped.
- Prawns: photo by Kolforn, CC BY-SA 4.0, cropped.
- Prunes: photo by Emőke Dénes, CC BY-SA 4.0, cropped.
- Quinoa: photo by Pom², CC BY-SA 3.0, cropped.
- Raisins: photo by Jacek Halicki, CC BY-SA 4.0, cropped.
- Rye: photo by FranHogan, CC BY-SA 4.0, cropped.
- Sardines or mackerel: photo by Friedrich Haag, CC BY-SA 4.0, cropped.
- Sesame (tahini): photo by Gilabrand, CC BY-SA 3.0, cropped.
- Soya yoghurt: photo by Veganbaking.net from USA, CC BY-SA 2.0, cropped.
- Spinach: photo by Nillerdk, CC BY 3.0, cropped.
- Squid: photo by Flickr.com user "deramaenrama", CC BY 2.0, cropped.
- Swede: photo by Mike Mozart, CC BY 2.0, cropped.
- Sweet potato: photo by Llez, CC BY-SA 3.0, cropped.
- Tofu: photo by DryPot, CC BY-SA 3.0, cropped.
- Tomato: photo by Softeis, CC BY-SA 3.0, cropped.
- Turkey: photo by Patrick Fitzgerald from Atlanta, GA, USA, CC BY 2.0, cropped.
- Walnut: photo by Ivar Leidus, CC BY-SA 4.0, cropped.
- Wheat (toast, pasta): photo by kallerna, CC BY-SA 4.0, cropped.
- White fish (cod, haddock): photo by sousvideguy.com, CC BY 2.0, cropped.
- Yoghurt: photo by Rainer Zenz, CC BY-SA 3.0, cropped.
The example photos of the sample family (Maya and Leo) are from Wikimedia Commons, in the public domain or CC0, made smaller: teddy bears by Cooper David, U.S. Fish and Wildlife Service, teddy by Unknown author, beach path by Irina Yankovaya, balloons by Hans Braxmeier, birthday cake by Brassluff, autumn leaves by Iurie Nistor, meadow by Gerda Arendt, butterfly by Peter Cooper Jr., snowy trees by Tsyganov Sergey, toy train by Thane Keller, sandcastle by Dinkum, baby shoes by Drew Hays.