Web Watchman is a web page change detection/notification tool that's free and extremely easy to use.
Have you ever came across something exclusive and limited you wanted to buy online but missed the opportunity by minutes because you were away? Maybe you’re someone who has a need to be updated with the latest gaming news, but your other responsibilities are stopping you from camping on the page.
With Web Watchman you can monitor your favorite pages without having to access them frequently and you can keep the change history of these pages.
Setting up a region of interest (ROI) for your monitoring task is very important, web pages nowadays often contain numerous dynamic elements, like dates, view counts, ads etc., while you probably don't care any of those, they can cause false alarm and you may get irrelevant notifications all the time. So make sure you only select the region you care about then you should be good to go! ;)