What are some alternatives?
Liner - Put simply, Liner is a virtual highlighter. It works on PDFs and webpages in the same way a regular highlighter works on books and magazine clippings. Read more about Liner.
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Paperpile - Clean and simple and reference management for the web. Sync your PDFs to Google Drive and cite your papers in Google Docs.
SendInBlue - Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.
Mendeley - Easily organize your papers, read & annotate your PDFs, collaborate in private or open groups, and securely access your research from everywhere.
GetResponse - Email marketing from GetResponse. Send email newsletters, campaigns, online surveys and follow-up autoresponders. Simple, easy interface. FREE sign up.