allTags was developed to manage large file sets efficiently. Time-consuming actions, like naming files and choosing folders, are replaced by fast tagging operations.
With built-in support functions, allTags avoids inconsistencies and speeds up file description and retrieval. allTags is 100% free to use.
TagSpaces - TagSpaces is an open source platform for personal data management. With TagSpaces you can manage and organize the files on your laptop, tablet or smart phone.
Synology Note Station - Without needing to spend money on Evernote, Synology Note Station provides a desktop client to organize all your random notes in one place.
TMSU - TMSU is a tool for tagging your files.
UpNote - A beautiful and clean cross-platform app for notes organizer
Tabbles - Tabbles use tags to organize and find files along with your colleagues.
Note Board - Productivity app. Save information like a sticky notes.