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.
Giftbit Payment API - Stripe for gift cards
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
ACH payments with Stripe - Accept bank payments with a few lines of code.
Better Uptime - We call you when your website goes down
Google Payment API - Enable an easy-to-use checkout experience for customers