Diigo has been around for a long time and is used by many. It has a free tier, which the majority of users use.
Let's have a look at their ahrefs backlink profile to gauge populatiry.
raindrop.io:
Backlinks
190,731Referring domains
2,748Backlinks
50,861,6146Referring domains
141,090The Most Popular Website traffic SEO endeavors webpage on Procedure in Backlink
Search Engine regards to site improvement, you can never have systems to support your motivation.
As you might possibly know the key to fruitful SEO endeavors is the measure of connections you construct that indicates back your site.
The more connections that the better your site will rank for a particular watchword.
One incredible approach to help construct joins for your site is through a social bookmarking list.
Some Best Social Bookmarking Destinations with their Positioning: