Thanks and good reference, greenyoda! It seems they just show diffs between the old and updated page, which has lots of false positive (e.g., change of some ad

Thanks and good reference, greenyoda! It seems they just show diffs between the old and updated page, which has lots of false positive (e.g., change of some ad text or date, etc) and is user-unfriendly. If I could create a cleaner app that detects and notifies not "any changes", but "any new records", would that be a good step forward and help lots of people? Wish I know who are using such services so I could possibly get an idea about potential customers...