AdWhistle is described as 'There are better things to do than manually check up on your Competitor's Facebook Ads. 😎 Just paste in your Competitors Facebook Pages you'd like to track and get daily reports on their Facebook Ads activity. 👁'. There are four alternatives to AdWhistle for Online / Web-based, SaaS and Google Chrome. The best alternative is Facebook Ads. It's not free, so if you're looking for a free alternative, you could try MyAdLibrary or Facebook Ad Library.
MyAdLibrary Helper is a free Facebook ad spy tool. It can provide you an advertising list, which is more convenient and practical than Facebook ad library. It can spy Facebook competitors' ads data, so as to better perform advertising analytics.