Credits and Licenses
Last updated October 27, 2026.
Opson is built on other people’s work. This page credits it and gives the licenses it comes under.
Food data
Nutrition values come from public food databases and from the people who add to them. They are estimates and can be wrong.
- USDA FoodData Central. U.S. Department of Agriculture, Agricultural Research Service. FoodData Central. fdc.nal.usda.gov. Public domain (CC0 1.0).
- Open Food Facts. Contains data from Open Food Facts, available under the Open Database License. Individual contents of the database are available under the Database Contents License.
- NEVO. Based on data from NEVO online version 2025/9.0, RIVM, Bilthoven. Dutch Food Composition Database.
Typefaces
Atkinson Hyperlegible Next, by the Braille Institute of America. Copyright 2020-2024 The Atkinson Hyperlegible Next Project Authors. Licensed under the SIL Open Font License, Version 1.1.
Young Serif, by Bastien Sozeau, sets the Opson wordmark. Copyright 2023 The Young Serif Project Authors (github.com/noirblancrouge/YoungSerif). Licensed under the SIL Open Font License, Version 1.1.
Open-source software
Opson uses these open-source libraries, each under the license named. The app lists every library in its builds, with each license’s full text, under More › Support and sharing › Credits and licenses.
| Library | License |
|---|---|
| Kotlin, kotlinx.coroutines, kotlinx.serialization, kotlinx-datetime, kotlinx.collections.immutable, atomicfu (JetBrains) | Apache 2.0 |
| Compose Multiplatform, Skiko, and the JetBrains builds of Lifecycle, Navigation and SavedState | Apache 2.0 |
| Android Jetpack (AndroidX), including Compose, Room, SQLite, DataStore, CameraX, Glance, WorkManager, Navigation, Lifecycle and the Health Connect client | Apache 2.0 |
| Protocol Buffers, as bundled in the Health Connect client | BSD 3-Clause |
| Ktor (JetBrains) | Apache 2.0 |
| Okio, OkHttp and Wire (Square) | Apache 2.0 |
| Kermit, Stately and SKIE (Touchlab) | Apache 2.0 |
| kotlin-inject (Evan Tatarka) | Apache 2.0 |
| kotlin-inject-anvil (Amazon) | Apache 2.0 |
| Koin | Apache 2.0 |
| Multiplatform Settings (Russell Wolf) | Apache 2.0 |
| cryptography-kotlin (Oleg Yukhnevich) | Apache 2.0 |
| Multiplatform Paging (Cash App) | Apache 2.0 |
| OpenTelemetry Kotlin | Apache 2.0 |
| Wiretap | Apache 2.0 |
| Gson, Guava ListenableFuture, J2ObjC annotations and Firebase encoders (Google) | Apache 2.0 |
| JSpecify | Apache 2.0 |
| supabase-kt | MIT |
| Sentry SDKs for Kotlin Multiplatform, Cocoa and Java | MIT |
The full license texts: Apache License 2.0, MIT License, BSD 3-Clause License.
Other software
On Android, Opson also uses Google’s ML Kit for barcode reading and Google Play services for in-app reviews, under Google’s terms for each.