MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Owlead - Grow your Twitter with valuable followers, effortless
Brevo - 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.
Fanbase - Fanbase helps enterprises grow a targeted audience of real people on Twitter.
SendPulse - Maximizing e-mail marketing open rates automatically
Swift Social - All-in-One Social Media Growth and Management Tool