Open-source Android apps without ads or trackers are available for most everyday tasks: encrypted messaging, offline maps, podcasts, video streaming, email, password management and notes. The apps below are listed in the Stackora catalog under Mobile Apps and are all released under open-source licenses. Each entry notes what the app does, its license and its publisher so you can check the source code yourself.
Messaging and calls
Signal-Android
Signal-Android is an open-source, end-to-end encrypted messaging app for Android. It lets you send private messages and make HD voice and video calls. It is licensed under AGPL-3.0 and published by signalapp. With around 29,000 GitHub stars, it is one of the most widely followed private messengers in the catalog.
Maps and navigation
Organic Maps
Organic Maps is a free, offline maps and GPS navigation app for Android and iOS. It is built for hikers, cyclists and travellers who want privacy without ads or tracking. Because maps work offline, it suits trips where mobile data is unreliable. The project is published by organicmaps.
Podcasts and media
NewPipe
NewPipe is a lightweight streaming front-end for Android. It plays YouTube, PeerTube, SoundCloud and Bandcamp content without Google services or an account. It is licensed under GPL-3.0 and maintained by TeamNewPipe.
AntennaPod
AntennaPod is a free, open-source podcast manager for Android. It helps you subscribe to, download and listen to podcasts in one app. It is licensed under GPL-3.0 and published by AntennaPod.
thunderbird-android
thunderbird-android is an open-source, privacy-focused email app for Android. It manages multiple email accounts in one place and offers an optional Unified Inbox. It is licensed under Apache-2.0 and published by thunderbird.
Passwords and two-step codes
Bitwarden Android
Bitwarden Android is an open-source mobile password manager and authenticator, built with Jetpack Compose and Kotlin. It is licensed under GPL-3.0 and published by bitwarden.
KeePassDX
KeePassDX is a free, open-source password and passkey manager for Android. It stores encrypted credentials in a single KeePass-format file. It is licensed under GPL-3.0 and published by Kunzisoft.
Aegis
Aegis is a free, open-source Android authenticator that generates HOTP and TOTP two-step verification codes, with encrypted vault storage. It is licensed under GPL-3.0 and published by beemdevelopment.
Notes and files
Joplin
Joplin is a free, open-source note-taking app for Windows, macOS, Linux, Android and iOS. It keeps notes in Markdown and syncs them with end-to-end encryption. It is published by laurent22 and is listed under Desktop Apps in the catalog.
MaterialFiles
MaterialFiles is an open-source, Material Design file manager for Android 5.0 and later. It supports root access, archives and network storage over FTP, SFTP, SMB and WebDAV. It is licensed under GPL-3.0 and published by zhanghai.
Nextcloud Android app
The Nextcloud Android app is a mobile client for accessing, syncing and managing files on a self-hosted Nextcloud server. It is licensed under GPL-2.0 and published by nextcloud. It is useful if you already run your own Nextcloud instance.
Terminal
Termux
Termux is a terminal emulator and Linux environment for Android. It can be extended with a wide range of installable packages. It has about 62,000 GitHub stars and is published by termux.
How to choose
Start with the category you use most. For private chat, Signal-Android is the direct choice. For passwords, pick one of Bitwarden Android or KeePassDX depending on whether you want a cloud-synced vault or a local file. Aegis covers two-step codes if you prefer a dedicated authenticator.
Check the license before you commit. Copyleft licenses such as GPL-3.0 and AGPL-3.0 require derivative work to remain open, which matters if you plan to modify or redistribute an app. Permissive licenses such as Apache-2.0 allow more flexibility.
Consider whether you need sync. Joplin and the Nextcloud app sync across devices, while MaterialFiles and NewPipe work locally. Organic Maps is the right pick when you need navigation without a network connection.
Finally, review the publisher. Projects maintained by an active organization, such as signalapp or bitwarden, make it easier to find up-to-date source code and issue trackers.
Recommendation
For most readers, a sensible starting set is Signal-Android for messaging, Organic Maps for navigation, AntennaPod or NewPipe for media, Bitwarden Android or KeePassDX for passwords, and Joplin for notes. Install one category at a time, confirm it meets your needs, and then add the next. You can browse more options in the Android apps catalog and the Mobile Apps category.