FOSS-Android

List of free and open-source alternatives to proprietary Android apps.

Feel free to contribute, fork and star this list. :)

Operating system

Proprietary app FOSS App
Android microG fork of LineageOS (if available), LineageOS
Google Play services microG
Google Play Store F-Droid (FOSS apps only), Aurora Store or Yalp Store (free Google Play clients)

Must have apps

Basics

Purpose of the app Proprietary app FOSS App
Maps Google Maps OsmAnd, F-Droid Maps (based on MAPS.ME)
Photo sync Google Photos Nextcloud Instant Upload
Browser Chrome, Firefox (has Chromecast libraries) Fennec F-Droid (Firefox fork), Waterfox (Firefox fork, note that not yet available from F-Droid), Tor Browser for Android, Bromite (Chromium fork, has Adblocking features as well)
Contacts Sync Google Contacts Nextcloud server with DAVdroid (guide)
SMS app Android Messages, your phone’s default Silence, QKSMS, Signal (open source, proprietary apk, has Google dependencies!)
Keyboard Gboard, SwiftKey, your ROM’s included keyboard Simple Keyboard, AnySoftKeyboard, AOSP Keyboard (included with LineageOS)
Launcher   Lawnchair or KISS Launcher (very minimalistic)

Productivity

Purpose Proprietary app FOSS App
Cloud storage Google Drive, OneDrive, Dropbox Nextcloud (selfhosted)
Email Gmail, your phone’s default Email app K-9 Mail, pEp
Calendar sync Google Calendar Nextcloud Calendar
Calendar client Google Calendar Simple Calendar
Tasks Wunderlist, Google Tasks Tasks (sync with Nextcloud Tasks with DAVdroid)
PDF Reader Google PDF Viewer Document Viewer, MuPDF

Instant messaging

Note: Most IM networks do not have FOSS clients or even open API for making those. 😥

Social media

Proprietary app FOSS App/Web-based alternative client
Reddit Slide
Twitter Use Twitter Lite mobile site and add to home screen
Facebook MaterialFBook (Improved mobile site wrapper for Facebook)
Instagram Use Instagram mobile site and add it to your home screen (more info on that)

Other

Proprietary app FOSS App
YouTube NewPipe (youtube client), YouTube Vanced (proprietary, modded version of the original YouTube client, no ads, etc.)
Google Assistant Just Search (just search but works for the button (long press home button)) or Fennec F-Droid/Firefox’s Assist Feature (opens url box inside the app)

DNS Resolvers

It’s important to choose privacy respecting DNS resolver.

Few ones I recommend can be found from my wiki.

Use DNS-over-TLS, DNS-over-HTTPS or DNSCrypt if possible to encrypt the connection.

You can change your DNS resolver for example in Blokada or Nebulo (DNS-over-TLS & DNS-over-HTTPS).