Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Novocall - Novocall converts web visitors into sales calls in seconds.
GoSquared Live Chat - Beautiful, simple, and free live chat for your website
OptinMonster - OptinMonster helps to convert abandoning website visitors into subscribers and customers.
Live Chat by Sumo.com - Instantly communicate with customers, prospects & visitors
Callpage - Turn website visitors into sales calls. Use CallPage and provide immediate free phone callback to your leads in 28 seconds.