Up Ninja is described as 'Monitor uptime,response timeandapdex indexes of your website or api for free and receive instant updates through e-mail or Slack with real time announcements. Don't leave your customers in the dark during downtime & outages of your website' and is a Uptime Monitor in the Network & Admin category. There are more than 100 alternatives to Up Ninja for a variety of platforms, including Online / Web-based, SaaS, Windows, Linux and Mac. The best alternative is UptimeRobot, which is free. Other great apps like Up Ninja are Better Uptime (Freemium), Pingdom (Paid), Freshping (Free) and PHP Server Monitor (Free, Open Source).
Dashboard with 50 Monitors, Checked Every 5 Minutes, Totally Free. Monitor HTTP(S), Ping, Port and check Keywords. Get alerted via e-mail, SMS, Twitter, web-hooks or push. View uptime, downtime and response times.
Pingdom web site monitoring and other infrastructure for you and instantly let you know when anything goes wrong. Measure uptime, downtime, and the performance of your website as experienced by visitors.
PHP Server Monitor is a script that checks whether your websites and servers are up and running. It comes with a web based user interface where you can manage your services and websites, and you can manage users for each server with a mobile number and email address.
StatusCake.com is a free website monitoring tool which allows users to track up to 10 websites and get alerted when their site is down or is having trouble. Downtime root cause analysis is included in the free plan to help users diagnose and fix issues.
Pinger is an uptime monitoring service which checks that your site is up and running and notifies you when it's not. It has contemporary UI and pleasant look along with a lot of useful features like notifying you via Slack, Telegram, Email or SMS.
Website/Server monitoring with fast notification via Web, SLACK or E-Mail on issues. What you get: 25 monitors, checked every 15 minutes. Now includes SSL-Certificate validation and port checks. Totally free!.