“Krita is a professional FREE and open source painting program. It is made by artists that want to see affordable art tools for everyone.”
“MyPaint is a nimble, distraction-free, and easy tool for digital painters. It supports graphics tablets made by Wacom, and many similar devices. Its brush engine is versatile and configurable, and it provides useful, productive tools.”
Blender: “is the free and open source 3D creation suite. It supports the entirety of the 3D pipeline—modeling, rigging, animation, simulation, rendering, compositing and motion tracking, video editing and 2D animation pipeline.”
Useful Blender add-ons:
“Wings 3D is an advanced subdivision modeler that is both powerful and easy to use. Originally inspired by Nendo and Mirai from Izware… Wings 3D offers a wide range of modeling tools, a customizable interface, support for lights and materials, and a built-in AutoUV mapping facility.”
Autodesk SketchBook is now free. Not avaiable on Linux. The mobile version has forced registration after the trial period is over. Desktop has no forced registration (the last time I checked)
$$$ Serif’s Affinity products are the best alternative to Photoshop, Illustrator and InDesign for the hobbyist. Unfortunately, it’s not available on Linux. I have to hang on to my macOS because of this.
qView: “An image viewer for viewing. No toolbars or distractions—pure space efficiency.”
PureRef: “The simple way to view and organize your reference images.”
digiKam: “…is an advanced open-source digital photo management application that runs on Linux, Windows, and MacOS. The application provides a comprehensive set of tools for importing, managing, editing, and sharing photos and raw files.”
XnConvert: “is a fast, powerful and free cross-platform batch image converter, It allows to automate editing for your massive photo collections, you can rotate, convert and compress your different images, photos and pictures easily, and apply over 80 actions (like resize, crop, color adjustements, filter, …). All common picture and graphics formats are supported…”
HandBrake: “…is a tool for converting video from nearly any format to a selection of modern, widely supported codecs.”
OBS: “Free and open source software for video recording and live streaming.”
fSpy: “Open source still image camera matching”
MeshLab: “the open source system for processing and editing 3D triangular meshes. It provides a set of tools for editing, cleaning, healing, inspecting, rendering, texturing and converting meshes. It offers features for processing raw data produced by 3D digitization tools/devices and for preparing models for 3D printing.”
“LibreOffice is a powerful office suite – its clean interface and feature-rich tools help you unleash your creativity and enhance your productivity. LibreOffice includes several applications that make it the most powerful Free and Open Source office suite on the market.”
“Obsidian is a powerful knowledge base that works on top of a local folder of plain text Markdown files.”
“Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, can be copied, tagged and modified either from the applications directly or from your own text editor. The notes are in Markdown format.”
7-Zip: “…is a file archiver with a high compression ratio.”
Jupyter: “Project Jupyter exists to develop open-source software, open-standards, and services for interactive computing across dozens of programming languages.”
Atom: “A hackable text editor for the 21st Century.”
Visual Studio Code: A free code editor from Microsoft.
“VirtualBox is a powerful x86 and AMD64/Intel64 virtualization product for enterprise as well as home use. Not only is VirtualBox an extremely feature rich, high performance product for enterprise customers, it is also the only professional solution that is freely available as Open Source Software under the terms of the GNU General Public License (GPL) version 2.”
Etcher: “Flash OS images to SD cards & USB drives, safely and easily.”
“Tails is a live operating system that you can start on almost any computer from a USB stick or a DVD. It aims at preserving your privacy and anonymity…”
Tor Browser: “Browse Privately. Explore Freely. Defend yourself against tracking and surveillance. Circumvent censorship.”
Jitsi: “More secure, more flexible, and completely free video conferencing”
Signal: Say “hello” to a different messaging experience. An unexpected focus on privacy, combined with all of the features you expect. (Cellphone required)
(No cellphone required)
“GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP). GnuPG allows you to encrypt and sign your data and communications; it features a versatile key management system, along with access modules for all kinds of public key directories. GnuPG, also known as GPG, is a command line tool with features for easy integration with other applications. A wealth of frontend applications and libraries are available.” Good overview of GPG for everyone of us. Click here.
“ProtonMail was founded in 2013 by scientists who met at CERN and were drawn together by a shared vision of a more secure and private Internet. Since then, ProtonMail has evolved into a global effort to protect civil liberties and build a more secure Internet, with team members also hailing from Caltech, Harvard, ETH Zurich and many other research institutions.”
“VeraCrypt is a free open source disk encryption software for Windows, Mac OSX and Linux.”
KeePassXC: “KeePass Cross-Platform Community Edition. The thing computers can do best is storing information.
You shouldn’t waste your time trying to remember and type your passwords. KeePassXC can store your passwords safely and auto-type them into your everyday websites and applications.”
Enpass: “A secure vault to store everything at one place using a single master password.”
I am not of the mindset that say or believe everything must either be open sourced or free. The reality is that someone somewhere has to sacrifice his or her time to work and code on the app that you and I use. I am also not a fanboy. I use what works. And I recommend tools that are useful and helpful.
As someone who is doing art as a hobby, free/open source apps are a tremendous help! Without Blender or Wings3D, I wouldn’t be able to learn or explore 3D. But when us hobbyists do make good money from the free or open source app(s) we use, it’s not only right, but godly, to contribute back financially [if] we’re able. Our Lord Jesus taught us that, “the laborer deserves his wages…” (Luke 10:7)
1 Corinthians 9:7-9 Who serves as a soldier at his own expense? Who plants a vineyard without eating any of its fruit? Or who tends a flock without getting some of the milk? 8 Do I say these things on human authority? Does not the Law say the same? 9 For it is written in the Law of Moses, “You shall not muzzle an ox when it treads out the grain.”
With that said, here are links to great apps that are either: Free, Open Source, costs around $100 or less and is hassle-free (no forced registration)