Application stores

Mobilism - Trusted Forum for downloading Modded APKs.
Requires Sign-up.

4PDA - Russian Forum for downloading Clean & Modded APKs, as well as discussion alike.
Requires Sign-up; Captcha Guide: #1/#2

SBenny - Another Forum for downloading Modded & Paid APKs. Has a point-based system which you can easily farm.
Requires Sign-up.

APKMirror - Website to download APKs dumped from the Play Store.

Aurora Store - Open-source Google Play Store client focused on providing privacy with a modern design.

F-Droid - Decentralized store for downloading libre (FOSS) applications. Material You client for the same.

Obtainium - App which allows you to install and update different applications directly from their release pages. Supports a lot of sources such as Github, Gitlab, F-Droid, Codeberg etc.

Browsers

Firefox Nightly | Fennec - Nightly and Stable versions of Firefox. Here's a Guide to add more extensions to Firefox Nightly.

IceRaven - Fork of Firefox which provides additional features, removes Mozilla Telemetry and adds more extensions to the current list, allowing you to make your own too.

Mull - Privacy oriented and deblobbed Firefox fork which enables many features upstreamed by the Tor uplift project using preferences from the arkenfox-user.js project.

Kiwi Browser - Chromium-based Web Browser that supports extensions.

Mulch - Security oriented and hardened web browser based on Chromium, with added patches from the Vanadium project.

FFUpdater - App for installing & updating various Firefox-based and Chromium-based browsers, with added automation capabilities.

Privacy & Security

PowerTunnel - Powerful and extensible DNS server with anti-censorship functionalities for Android.

AdAway - Open-source mobile ad-blocker with a focus on privacy.  
This app benefits from having root access.

Bitwarden - Open-source & self-hostable password manager. Material You client for the same, with better performance and additional features.

KeePassDX - Open-source password manager forked from KeePassDroid; allows one to store passwords in an encrypted database locally.

File Managers

MiXplorer - Fully-featured Android file manager that supports multiple cloud storages and server protocols.

Material Files - Android file manager with the Material You design, can also be used as an FTP server or an SMB/SFTP client.

SD Maid 2/SE - Powerful file management tool for Android that specialises in freeing up space and removing unwanted data.
SD Maid 2/SE isn't feature complete as it is an in-progress reimagination of SD Maid to work better with newer phones.

Round Sync - Fork of RCX; an Android port of Rclone that has the ability to manage files on several different cloud service providers.

Video/Music

Seal - Audio/Video Downloader GUI for use with yt-dlp's supported platforms.

mpv for Android - Open-source media player that supports a wide variety of media file formats, audio and video codecs, and subtitle types.

VLC for Android - Another open-source media player which has the ability to play various media formats, network streams etc. along with other useful features. Mod which allows Monet theming for the same.

CloudStream - Open-source app for streaming and downloading media along with a fully-fledged extension system.

xManager - Manage and install all versions of the Spotify app, unlocking features such as ad-blocking and skipping tracks.

Seeker - Open-source Soulseek client for Android which supports various features such as downloading, searching, sharing, messages, chat rooms, port forwarding etc.

Murglar - Android client for playing and downloading music from services such as Deezer, SoundCloud, VK and Yandex music. Refer to this guide for obtaining Deezer ARLs to use with Murglar.

Torrenting

LibreTorrent - Open-source Torrent client for Android.
LunaSea - Usenet/Torrent manager. Useful for those who utilize seedboxes.

Mods

ReVanced - Android App patcher that provides patches to popular apps such as YouTube, Twitter and Reddit.
It requires the need of a microG client for YouTube and YouTube music if your device does not have root access. At the moment, the most compatible microG manager with ReVanced according to the community is Vanced MicroG, but it may be replaced in the future.

Aliucord - Plugin-based Discord (Kotlin - below 126.21) client mod for Android. Note that Aliucord only supports versions before the React Native update (all versions before 126.21)

Miscellaneous

Lucky Patcher - Android app modifier which can be used to remove license verification, advertisements, change permissions, unlock in-app purchases etc. This app isn't open source so giving it root access to use some of it's features is your responsibility!

GameGuardian - A game/cheating app for Android. Similar to Cheat Engine on PC.
This app isn't open source so giving it root access to use some of it's features is your responsibility!

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