office products:
libreoffice - office suite ~ [Win,Mac,Linux,Android]
private, free & open source office suite to replace Microsoft Office & Google Docs. Includes = Writer [Word], Calc [Excel], Impress [Powerpoint], Draw [Visio/PDF], Base [Access DB], Math {unique for math calculations}.

onlyoffice - office suite ~ [Win,Mac,Linux,Android]
private, free & open source office suite to replace Microsoft Office & Google Docs (also works Online in browser). Includes = Document [Word], Spreadsheet [Excel], Presentation [Powerpoint], Diagram [Visio], EBook {unique for ebook reading}, PDF/Form Creator [PDF editor]. It is also GDPR, HIPPA, and other security protocol compliant.

thunderbird - email/calandar client ~ [Win,Mac,Linux,Android]
private, free & open source email client, calander, and productivity program. securily linnk and check all email accounts, sync calander events and install privacy extensions.

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music/video players:
vlc - [Win,Mac,Linux,Android,iOS]
free open source cross-platform multimedia player and framework that plays most multimedia files, and various streaming protocols. it can rip/burn cds, stream, cast, manage subtitles and audio files metadata.

mpv - [Win,Mac,Linux,Android]
free open source media playerr, with minimalistic ui, keyboard or commandline controls, low resource requirement. perfect for older machines or a small sive vlc alternative. slight learning curve with controls

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notes:
Obsidian - [Win,Mac,Linux,Android]
private, free & open source notetaking application. a huge library of plugins, features, organization with a huge community behind it. syncing across devices does cost a subscription or you can use a cloud server to backup and restore vaults from.

Notesnook - [Win,Mac,Linux,Android]
private, free(limited), & open source pasic note taking application with text markdown.

Notion - Notes/Mail/Calendar ~ [Win,Mac,Linux,Android,iOS]
private, free & open source notetaking application. a huge library of plugins, features, organization with a huge community behind it. syncing is free but there are now included ai features *that can be disabled).

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misc:
libresprite [win,mac,linux]
free and open source aseprite replacement. creates and animates your sprites