Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
Nudgify - Nudgify is a Social Proof App that includes FOMO, Urgency and Review Nudges. Adding Social Proof notifications to your site helps you build trust and increase conversions on Shopify, Wordpress or any other platform.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
NotificationX - Best social proof and FOMO marketing solution for WordPress to increase conversion rates.
Better Uptime - We call you when your website goes down
Proof - Website conversion rate optimization and visitor monitoring