HelpForShopping - Improve your sales performance by helping users find the most suitable product for them

Q-Stats - Get free marketing insights for every question on Quora.

tawk.to - tawk.to is a free live chat app that lets you monitor and chat with visitors on your website or from a free customizable page

Site Rank Data - View historical rank information of websites via time series charts.

Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.

HypeStat - HypeStat is free statistics and analytics service, where you can find information about every website.