Thunderclap is described as 'crowd-speaking platform that helps people be heard by saying something together. If enough people support it, Thunderclap will blast out a timed Facebook Post or Tweet from all your supporters, creating a wave of attention' and is an website in the social & communications category. There are three alternatives to Thunderclap, not only websites but also apps for a variety of platforms, including Shopify, SaaS, Squarespace and Weebly. The best alternative is Elfsight, which is free. Other great sites and apps similar to Thunderclap are SociableKIT and Pack.org.
SociableKIT is a website plugin that will help you display social media content on your website. It allows you to customize the look & feel of your social media contents and display them on your website automatically.