ChangeDetection (and other sites like it) are a powerful tool for tracking what your competitors are up to. While at RedLaser, I’d use this kind of tool to watch some of our competitors, and particularly their feature lists. Whenever they launched an update, I got a notification and it was far more reliable than Google Alerts.
If you’re trying to monitor your competition more broadly — think funding updates, acquisitions, or other major news — the best service I’ve seen (without a hefty fee, like Mattermark) is Owler. Owler has a number of frustrating UI bugs, but once you’ve subscribed to companies to follow, you can use it almost entirely by email, and it works really well.
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