This efficient browser add-on blocks ads, trackers, and malware by default employing various filter lists, acting as a comprehensive wide-spectrum blocker.
As you browse the internet, sites you visit can attempt to take screenshots of your computer as a pixel-by-pixel unique digital "fingerprint" of you & and your devices. This is called canvas fingerprinting.
Protects you against tracking through "free", centralized, content delivery. It prevents a lot of requests from reaching networks like Google Hosted Libraries, and serves local files to keep sites from breaking. Complements regular content blockers.
The EU regulations require that every website must get user's permission before installing cookies. Imagine how irritating that becomes when you surf anonymously or if you delete cookies automatically every time you close the browser.
Makes every page (or only pages that you want) to have light text on dark background. Exact colors are customizable.
Organized List is further Down
gPodder downloads and manages free audio and video content ("podcasts") for you. Listen directly on your computer or on your mobile devices.
gpodder.net is a libre web service that allows you to manage your podcast subscriptions and discover new content. If you use multiple devices, you can synchronize subscriptions and your listening progress.
Tidal is the world’s first music service with High Fidelity sound quality, High Definition music videos and Curated Editorial by music journalists, artists and experts, making for a simply superior experience.
An open-source, ad-free front-end to YouTube offering video downloads, audio-only mode, and subscription management without JS or registration.
Experience YouTube ad-free on desktop with enhanced privacy. FreeTube prevents Google tracking and works seamlessly across Windows, Mac, and Linux.
Distraction-free note-taking app with categories, Markdown formatting, favorites, and RESTful API. Integrates with Nextcloud clients for seamless syncing.
Plain text notepad with markdown support and todo list manager for Linux, Mac OS X and Windows, that works together with the notes application of ownCloud.
Free and open-source office suite with advanced word processing, spreadsheets, presentations, vector graphics, math formula editor, and database tools.
A free and open source podcastmanager for Android, allowing you to subscribe to podcasts (via iTunes database & OPML), automatically download episodes using powerful mechanisms and listen to them the way you like (speed, balance adjustments, etc).
Privacy-focused, open-source email app offering encryption, unlimited accounts, customizable features, unified inbox, and low data usage.
Vanced is a modded version of YouTube with many features such as adblocking, background playback, PiP mode and several other customizable ones.
For iOS - Omnifocus
Tasks is libre open-source software, based on the original source code from the popular Astrid Tasks & To Do List! Tasks is easy-to-use, feature-packed, flexible and customizable, and synchronizes with a variety of services.
Track your tasks and projects in a plain text file, todo.txt. A todo.txt is software and operating system agnostic; it's searchable, portable, lightweight and easily manipulated.
sleek is an open-source (FOSS) todo manager based on the todo.txt syntax. It's available for Windows, MacOS and Linux.
Merkuro is a calendar and contact application that allows you to manage your tasks, events and contacts. Merkuro supports both local calendars as well as a multitude of online calendars: Nextcloud, Google® Calendar, Outlook®, Caldav, and many more.
Ardour is a hard disk recorder and digital audio workstation application. Record, edit, and mix on Linux, Mac OS X, and Windows.
Intuitive multi-track video editor with robust hardware-accelerated support; offers chroma key, color grading, and extensive audio/video format compatibility.
Free open-source multi-track audio editor and recorder with 32-bit float processing. Supports many formats and plugins for Windows, macOS, Linux.
Open source vector graphics editor supporting SVG with features like custom brushes, pressure sensitivity, and layer management across multiple platforms.
Advanced image manipulation tool offering comprehensive tools for photo retouching, composition, and batch processing in a free package.
The powerful, easy-to-use, and customizable micro-site that gets your content to your consumers in fewer clicks.
Open-source password manager with AES-256 encryption and device sync. Store and access encrypted logins across platforms like iOS and Android.
On-premises file sync, universal access, integrated collaboration, real-time communication with privacy and data control focus.
LBRY is the first digital marketplace to be controlled by the market's participants rather than a corporation or other 3rd-party.
Desktop peer-to-peer (P2P) application that allows you to buy and sell bitcoins in exchange for fiat (national currencies), or alternative crypto currencies
Deluge is a full-featured BitTorrent client for Linux, Unix and Windows. It is written in python, uses 
libtorrent (rasterbar) at its core and GTK for the main user interface along with web and console interfaces for advanced client/server...
Mail, SMS, Group Chat
Matrix defines a set of open APIs for decentralised communication, suitable for securely publishing, persisting and subscribing to data over a global open federation of servers with no single point of control.
Mattermost is a secure, open source platform for communication, collaboration, and workflow orchestration across tools and teams.
FluffyChat is an open, nonprofit and cute matrix messenger app for Ubuntu Touch, Android and iOS.
Note: I use NSSM to run Duplicati really well.
Comments
What a great list. And? Looks like your in production of sorta... I cant wait to try Ardour (IIRC... the name). Thank you!! Probably found another one or more (FOSS Cross-Platform) that will be a badass wrench in the ole toolbelt!
P.s. i think i saw something like scrcpy recently on Github > Android > Sort by? most stars - kinda near the top tgat aounded like 'uh.. whuuuat? how was i unaware of THIS?!?! I think it was an actual app, perhaps with GUI, as opposed to a 'Library'(?) or aomething only developers would know how to use... or... understand... (without years or skills or both together). Fun Regards~