When comparing Org mode for Emacs vs LifeDigger, the Slant community recommends Org mode for Emacs for most people. In the question“What are the best personal Knowledge Base apps?” Org mode for Emacs is ranked 1st while LifeDigger is ranked 18th. The most important reason people chose Org mode for Emacs is:
Emacs runs on all platforms, Windows, Linux, OSX, even Android and IOS
Question Ranking
Pros
Pro Cross platform
Emacs runs on all platforms, Windows, Linux, OSX, even Android and IOS
Pro Libre/open source
Pro Can be as simple or as complex as you want
Org mode started out as a simple outlining/note taking app. Then each outline heading can optionally be a TODO list item. And if you desire, you can add SCHEDULE and DEADLINE dates. (Schedule being the date you'd like to start the item.) You can customize the TODO states to add things like DELEGATED, WAITING, BLOCKED, etc.
Pro Exports data to PDF, LaTeX, HMTL and other
You can even build presentation or blog from your data
Pro Supports tables with formules (quite powerful!)
Pro Inline image displaying
Pro Plain text data storage
Future-proof.
Pro Uses Emacs
Pro Free but copyrighted
Pro Fast interaction
Once muscle-memory sets in, can be much faster to use than a point & click program.
Pro Review mode
Review your knowledge and strengthen your memory thanks to the spaced-repetition effect.
Pro Intuitive
LifeDigger fills in the blanks in your organization scheme.
Pro Tags
Use tags to organize your knowledge and get rid of traditional organization schemes.
Pro Cross-Links
Link your information together in a Wiki style.
Pro Good dashboard
Even though the project is young, efforts have been made to provide graphics of your activity on the PKB, and the current state of your knowledge
Pro Flash-cards
Trigger your long time memory with flash-cards.
Pro Mind Map
Get insights on your knowledge and picture your mastery level.
Cons
Con Obtuse documentation
The documentation assumes a level of understanding of basic Emacs usage that not all users may have.
Con Complicated to get started
Con Difficult to use as a database
For example, if you need to quickly populate client details on quotes, unfortunately its easier to find, copy & paste.
Con Uses Emacs (for those who prefer vi, menus, etc.)
Con PDF export can be difficult
Latex assumes you're a (compliant) student, have to do a lot of research to get what you want out of it.
Con Is a webservice
If the provider decides to shut down or charge money, your ideas are lost.
Con Website shows nothing without JavaScript
Hence you first need to trust the provider to find out what it offers.