SPY-service: PowerAdSpy 

If you’re unsure how to build your marketing strategy, PowerAdSpy will help you do it based on the experience of top-performing competitors.

PowerAdSpy not only lets you track ads, but also provides detailed statistics and analytics regarding their performance. All of this can help you better optimize your own campaigns — even, as stated on their site, without the need for additional split testing (though honestly, you should still run tests — don’t fall for the slogans).

The PowerAdSpy database includes over 350 million ads from 100+ countries. And more than 250,000 new ads are added daily.

A free trial is available so you can evaluate the tool before purchasing. The basic plan starts at $69/month, while the platinum plan will cost you $279/month.