Building upon the strengths of award-winning Diigo V3, widely regarded as one of the best and most popular social bookmarking and web annotation services, Diigo V4 makes the following significant upgrades:

1. Archiving Snapshots of webpages (* Premium-only feature):
   
   
1. While bookmarking a page to Diigo, you can now choose to upload and capture a snapshot — including dynamic and password-protected content. For each snapshot in your archive, Diigo offers HTML and screenshot (pic) formats. Other online file formats such as PDF, Word (under IE browser), etc can also be archived.
   
   
2. Capture multiple versions of the same URL — snapshots, of moments in time. "A personal wayback machine", the way you want it.
   
   
3. Archiving dynamic web pages makes bookmarking so much more useful: you can now archive your online receipts, or that promotion ad you see. Or,  you can archive your stock portfolio periodically so you can easily see how it evolved over time.
   
   
4. Diigo 4.0 now enables you to search your entire Library, including archived items
   
   
   
2. Streamlined and customizable user interface
   
   Diigo V4 UI has been streamlined to focus Diigo as a powerful tool for research, sharing and collaboration.
   
   
1. Three of the top menus, My Library, My Network, and My Groups, are directly tied to the key value propositions of Diigo, namely,
   Research, Share, and Collaborate, respectively.
   
   
2. Users now have a trio of display modes,  Compact, Standard, Power Edit,  to choose from, making it possible to satisfy diverse users' needs and preferences
   
   
   
3. Improved Annotations features and user interface
   
   
1. Multicolored highlight (yellow, blue, green, pink) is now available!
   
   
2. Introduce a new "highlighter pen" function:  click the "Highlight" button on the toolbar, your mouse will instantly become a highlighter pen! Once you finish highlighting with the pen, click the "Highlight" button again to disable.  (Note:  previous right-click Highlight menu still available as it is.)
   
   
3. UI / icon changes in Diigo's 2 kinds of sticky notes: in-situ (associated with a highlight) and floating note (freely positioned to a page).  Sticky note window is now resizble by dragging the right hand corner.  See tutorials in action
   
   
4. Get more from Diigo groups
   
   Diigo Groups UI has been completely revamped to allow increasing capability for knowledge repositories and collaboration
   
   
1. Unified view — forum discussions and bookmarks are no longer separated to encourage more interaction. For those who prefer a separated view, filters are handy.
   
   
2. Share your snapshots: now, when you share a bookmark to a group, the group also gains your archive of that bookmark. So imagine a private group for head hunters, taking snapshots as they trawl various networks for potential candidates. Now: snapshots of candidates' profiles can be shared quickly, and with ease.
   
   
5. Facilitating personal learning networks - sharing content, and engaging in conversation around content
   
   
1. Follow, or followed — simple, one-directional, Twitter-like. Diigo V3's bi-directional friending is laid to rest: all previous relationships are converted to the new scheme, and from there you can refine the list of people who you follow.
   
   
2. My network — a stream of bookmarks and annotations from people that you choose, with easier methods of conversation.
   
   
6. Faster and better search:
   
   We know how important it is to let you find exactly what you need easily and quickly. You can now easily switch between several search modes in "My Library":  
   
   
1. Filter by tags  --  this gives you the most specific search results, but also might not find what you are looking for, in case you failed to tag or forgot how you tagged.
   
   
2. Search by full-text (* Premium only feature) -- this searches everything in bookmarks, including snapshots, titles, annotations, tags and URLs. Naturally, this search mode gives you a lot more results. In case it gives you too many results to find what you need quickly, you can try the next search mode.
   
   
3. Search by titles, tags, annotations, and URL --  this basically searches everything in bookmarks, except snapshots themselves.
   
   
4. Advanced search -  for power users out there, you can of course directly head towards the "advanced search" options.
   
   
7. Innovation and attention to detail:
   
   We continue our fanatical focus on delivering the best user experience through innovation and attention to details. Examples of other improvements include:
   
   

1. Multi-word tags — site-wide support for space-separated multiple word tags.
   
   
2. Better ways to add and edit your tags.
   
   
3. Diigo meta: for each bookmarked item, a useful blend of key features and related information
1. link to an annotated view
2. link to snapshots etc. in the archive for the item
3. bookmarking and annotation history
   
4. users' comments and highlights, group annotations etc.
5. looking ahead: aggregation of other information relating to the URL.
   
   
4. Numerous other improvements in the UI and behind the scenes.
   
   
5. 1st of our smart phone apps are coming soon (pending App Store approval) - stay tuned!