First thing to do is install F-Droid which is an open source alternative to Google Play that only contains FOSS (Free and Open Source Software) apps. This way you can easily update the apps and find new ones... All the Android apps are available on F-Droid unless otherwise stated.
One common feature among the following apps is being privacy-friendly.
This list isn't in anyway exhaustive so feel free to ask for other apps.
If you don't like F-Droid's design then you can use an alternative client like Aurora Droid. Aurora Droid also comes with a lot of repositories that you can easily enable.
Repositories: F-Droid is very strict about the apps that are included in the official repository but there are other repositories you can add to have access to more apps. Izzy's repo is a popular one which you can easily add.
Fennec which is Firefox on F-Droid
Lightweight, background playback, video or audio download, no accounts needed, subscriptions and more.
Peertube is a decentralized Youtube alternative:
If you still have to use apps not avialable on F-Droid
If you wanna completely get rid of Google Play Services, check microG out.
Lemmy is a federated Reddit alternative:
A completely new version of Twidere, called TwidereX, is being actively developed.
There is now an app that support Nitter (a FOSS front end for Twitter):
Mastodon is a federated Twitter alternative:
ProtonMail The app isn't available on F-Droid but ProtonMail is open source and very good privacy-wise.
::: spoiler spoiler There are no FOSS search engines but I absolutely recommend DuckDuckGo for privacy. Google is evil, folks. :::
You should absolutely use one.
Very convenient and easy to use, lots of features, group voice chats similar to Discord's and more. It isn't E2E encrypted by default.
Joplin The app isn't available on F-Droid but it's open source.
OpenScan follow the instructions here to add Izzy's repository to F-Droid
Remove metadata from your pics before sharing them. Very important for opsec.
Lichess avialable on Izzy's repository.
Avoid using Facebook if possible
Avoid using Instagram if possible and use Pixelfed instead
Pixelfed is a federated Instagram alternative
Don't engage with gam*rs!
Use the search feature in F-Droid, :LIB: I use an RSS bot on Matrix so I don't know about the RSS apps on F-Droid and there are a lot.
This is on my to-do :)
you can use PWAs (Progressive Web Apps) instead by clicking on Add To Home screen in Firefox's main menu.
Which apps you still can't replace? Do you have any FOSS recommendations? Questions?
Huge thanks to @kitten & @SirLotsaLocks for their contributions to this post!
@Pirate
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