No, it did not help sales at all.
More recently I’ve done a full study that I hope will help answer your question. One of my bigger apps has automatic updates, so I decided to use this. Basically, if someone installs version 1.0 of my app (which isn’t obtainable anymore unless you pirate it), then it will give you a fake update which essentially locks the app until you prove your purchase. It also sends me the URL of the installation.
Sample size: 230
- About 15% of these people reinstalled the pirated edition and avoided the update.
- About 70% of them installed a different app from a different person instead, or took down the website entirely.
- Only 1 person purchased a license to the app.
Then, of that 15% who reinstalled it, I sent DMCAs to the whois admin email of about 60% of them (the rest had whois privacy protection). All of these individuals did take down the product, none of them purchased it.
So basically. I made $15 USD off many days of work. Not worth it IMO, I could have spent the time working on new stuff.