A list of apps I use on GrapheneOS, but most also make sense on other operating systems.
Install "F-Droid Basic" and Obtainium, add a few repos to F-Droid by searching for "F-Droid known repositories"
Use Firefox Translation Models for on-device translation on Android. This is app is not developed by Mozilla. It depends on firefox translation models and Tesseract OCR.
Offline text translation, text recognition from images and speech-to-text, can be used as systemwide speech-to-text provider!
Introducing Fossify Contacts - the next evolution in contact management. Poised to redefine how you manage your contacts, our app combines simplicity with advanced features, tailored for both personal and professional use.
This app is meant for users that don't want to synchronize their contacts online, but want to keep them local to the phone. Though there is a problem, if you brick your phone, you might lose all your contacts.
Sync your contacts offline to a folder, which is synced with Syncthing. Runs in the background and just works
Libre Contacts Backup is a FLOSS native Android contact backup app that works entirely offline, encrypts your backups, and has no third-party runtime dependencies.
Modern alternative to SD Contacts, allows saving tags and other metadata, and encrypted backups. Built with AI, might have bugs.
Privacy-first PDF utility (Zero-Server Architecture). Merge, split, compress, and edit PDFs 100% locally on your device. No uploads, no servers, no tracking.
New open source PDF editing tool. Very promising but might still have bugs.
modern and featureful clock that supports "direct boot", so alarms work if the device is not unlocked yet.
Xodo is the ultimate cross-platform PDF viewer and annotator. Powerful, fast, and optimized for all phones and tablets, Xodo makes it easy to access, edit, share, sync, manage, sign, and more.
works offline but full of ads. needed to "sign" PDFs (Add an image), fill forms etc. Files can be shared to "SaveLocally" to avoid the locked "export" feature
ShareAsQR is a lightweight Android app designed to make generating QR codes as simple and efficient as possible. Unlike other apps, ShareAsQR focuses solely on QR code generation, keeping the app small and fast.
For sharing passwords, links etc. without any network connection.
Android app that allows you to record audio from the microphone and adjust it using the equalizer.
Needed for recording loud concerts etc.
A privacy-focused currency converter for Android that works completely offline. No account, no tracking, no analytics — just exchange rates in your pocket.
Needed for sharing files between main profile, private space or work profile. Also useful for bad apps that don't allow exporting files normally.
The app is free on F-Droid and on GitHub but you can buy it on the Google Play Store to support the developer.
allows to dim screen darker than Androids pretty useless "extradark". Many apps refuse to work with the overlay on though, like KeepassDX.
Free the internet from data collection with Mullvad VPN – a service that helps keep your online activity, identity, and location private. Only €5/month.
Provides cropping, filters, EXIF editing, background removal, PDF editing, batch processing, custom filters, OCR, encryption, and format export.
Snapseed is a photo enhancement and sharing app with a powerful suite of imaging filters and tools for anyone, anywhere, to transform any image into an extraordinary photo.
offline, few things missing from ImageToolbox like perspective, contrast/brightness
SoundAura is an open source ambient sound app. It does not include any audio tracks to save on download size, but allows users to add local files from their device and play any (reasonable) number of them concurrently, with individual volume controls for each track.
An implementation of the system-wide JamesDSP audio processing engine for non-rooted Android devices.
It doesn't use the Android builtin Equalizer and has a lot more functionalities.
Add audio effects to most music players, like Equalizer, Soundstage wideness or dynamic bass boost.
DroidFS is an alternative way to use encrypted overlay filesystems on Android that uses its own internal file explorer instead of mounting virtual volumes. It currently works with gocryptfs and CryFS.
Store Files in an encrypted container, works with syncthing and goCryptFS on another machine
Monerujo is the first app for managing and using Monero wallets on Android. It is a lightwallet: it uses remote nodes for synchronizing to the Monero blockchain while keeping all your private data on your device.
Signal but better. Combine with MollySocket and a unifiedPush distributor like "Sunup" to save batterylife without Google tracking
Markor is a TextEditor for Android, versatile, flexible, and lightweight. Markor utilizes simple markup formats like Markdown and todo.txt for note-taking and list management. It is versatile at working with text; it can also be used for keeping bookmarks, copying to clipboard...
get control over which app to use for which link. using link cleaning can slow it down a lot.
Jerboa is an app for Lemmy, a federated reddit alternative. Jerboa is made by Lemmy's developers, and is free, open-source software, meaning no advertising, monetizing, or venture capital, ever.
A free and cloudless replacement for your gadget vendors' closed source Android applications. Supports Pebble, Mi Band, Liveview, HPlus and more.
he Flora Incognita App enables you to identify plants automatically quickly, easily and accurately .
proprietary but "okay for privacy".
Feeder is a fully free/libre feed reader. It supports all common feed formats, including JSONFeed. It doesn't track you. It doesn't require any setup. It doesn't even need you to create an account!
Identify bird sounds in real time with this Android version of BirdNET. Bird sound recognition for more than 6,000 species worldwide.
local model, alternative to "Bird.net"
dict.cc is not only an online dictionary translating from English and German to 21 languages. Its an attempt to create a platform where users from all over the world can share their knowledge in the field of translations.
proprietary but privacy friendly. You can change it to offline after downloading dictionaries. Use Ironfox for full text translations, "about:translations".
Öffi is an Android app that tells you where and when trains and buses go, including delays and replacement bus services for more and more transport authorities in Europe and worldwide.
“Data Monitor" is a user-friendly, free and open source app for you to manage your data usage. “Data Monitor" helps you to accurately measure your daily data traffic, and analyze the data in a way easy to understand.
use the widget to show how much mobile data you have left.
FitoTrack is a mobile app for logging and viewing your workouts. Whether you’re running, cycling or hiking, FitoTrack will show you the most important information, with detailed charts and statistics. It is open-source and completely ad-free.
NeoStumbler is an application for collecting locations of Wi-Fi networks, cell towers and Bluetooth beacons to Mozilla Location Services.
contribute to BeaconDB, privacy friendly network location
Help to improve the OpenStreetMap with StreetComplete by completing quests which consists of simple questions about the world around you.
learn to contribute to OpenStreetMap, you will see your changes in OSMAnd and CoMaps after a while
Warn if you are followed by airtag or similar. Use if you fear that people want to surveill where you are.
Flash .iso files to usb sticks, like for installing a Linux distro
LibreTorrent is a Free as in Freedom torrent client for Android 4 and later, based on libtorrent. Download and share files directly on your device.
Android client for peer-to-peer file sharing built with C#, enabling searching with filters, wishlist, downloads, messaging, chatrooms, port forwarding, and full open-source access with no ads.
For finding and sharing music and more, use a VPN!
This list will never be complete, but aims at giving you a headstart in a free Android experience!
Comments
I'd like to add DekuSMS and CopySMScode
DekuSMS just showed a black screen for me a while back, but otherwise I agree