Zotero - Zotero is a free, easy-to-use tool to help you collect, organize, cite, and share research.
Raindrop.io - All your articles, photos, video & content from web & apps in one place.
Diigo - Diigo is a powerful research tool and a knowledge-sharing community
Pocket - When you find something you want to view later, put it in Pocket.
Weava - Workspace to highlight, organize & collaborate on your research articles.
Stash.ai - AI-powered, cross-device bookmarking