Altmetrics are alternative metrics derived from open web resources.
They measure the number of times a research output is tweeted, downloaded, viewed, discussed etc., pointing to the public or social
visibility of the output.
Reveals impact of anything with a digital object identifier (DOI). Full version requires subscription, but Almetric It is a free bookmarket for Chrome, Firefox, and Safari. Currently only works on Pubmed, arXiv or pages with a DOI; publishers must embed Google Scholar friendly citation metadata.
ImpactStory (available only through subscription):
Web-based application that makes it easy to track the impact of a wide range of research artifacts (such as papers, datasets, slides, research code). The system aggregates impact data from many sources, from Mendeley to GitHub to Twitter and more, and displays it in a single, permalinked report.
PlumX (available only through subscription):
PlumX collects impact metrics in five major categories: usage, captures, mentions, social media, and citations.
Provides PLoS Views, PLoS PDF downloads, PLoS XML downloads, PMC views, PMC PDF downloads. Citations – PubMed Central, CrossRef, Scopus, WoS, Google Scholar. Social Network – CiteULike, Mendeley, Twitter, Facebook, and Blogs and Media.