Diffmon is a website monitoring tool that can play two distinct roles. On the one hand, webmasters can use it to be alerted when any trouble arises and theirs sites go down. On the other hand, if you are a member of the general public you can employ this monitoring tool in order to be informed when new content has been added to your favorite sites the very moment that happens.
In the first case, webmasters can not only be notified about uptime and downtime, but also about changes in their web content. This makes it very easy for them to learn if someone has hacked their sites. And in the second case, users can set down a lot of parameters and be notified about big updates only, Notifications themselves can take up three shapes: messages via email, messages via SMS, and communications through RSS feeds. There are three different plans for you to have your pick: “Free”, “Basic” and “Business”. The free one comes with unlimited (and free) up/down alerts via SMS. If you want to be notified about content changes, then you will have to go for any of the two paid plans.