Call me old-fashioned, but I’ve always enjoyed using Apple’s built-in Mail app for iOS. Sure, the app itself admittedly lacks some advanced features you can readily find on third-party email clients, but the overall user experience is simple, serviceable, and relatively straight forward. I’ve tried any number of email clients over the years, but I always seem to revert back to Apple’s own Mail app for iOS.

While I can certainly understand the desire to use a more fleshed out email client for iOS, you’d be well-advised to do some research before downloading certain email clients from the App Store. As laid out in a new and eye-opening article on Motherboard, a number of popular email apps — including one that can be found in a list of top 100 Productivity apps — have been busy scraping user emails and selling anonymized data to third parties.

The report reads in part:

The popular Edison email app, which is in the top 100 productivity apps on the Apple app store, scrapes users’ email inboxes and sells products based off that information to clients in the finance, travel, and e-Commerce sectors. The contents of Edison users’ inboxes are of particular interest to companies who can buy the data to make better investment decisions, according to a J.P. Morgan document obtained by Motherboard.

Though Edison’s website includes a privacy page where the company lays out what it does with user data, there’s a good chance that many Edison users are wholly unaware of the company’s practices. Incidentally, Edison does provide users with a way to opt-out of this data collection without any consequences to the user experience.

Notably, there are a number of other apps that collect user data in questionable ways, including an app called Cleanfox which is designed to let users seamlessly unsubscribe from unwanted newsletters with just one click.

To be clear, there’s no reason to be running for the hills here. Rather, the report above illustrates that privacy-minded users should be a bit more cognizant of the third-party email apps they choose to use.

Lastly, Edison, in response to the Motherboard report, put out a new page on its website in an effort to be more transparent about what it’s doing behind the scenes.

To keep our Edison Mail app free, and to protect your privacy by rejecting an advertising-based business model, our company Edison Software, measures e-commerce through a technology that automatically recognizes commercial emails and extracts anonymous purchase information from them. Our technology is designed to ignore personal and work email, which does not help us measure market trends.

The full explanation can be viewed over here.

A life long Mac user and Apple enthusiast, Yoni Heisler has been writing about Apple and the tech industry at large for over 6 years. His writing has appeared in Edible Apple, Network World, MacLife, Macworld UK, and most recently, TUAW. When not writing about and analyzing the latest happenings with Apple, Yoni enjoys catching Improv shows in Chicago, playing soccer, and cultivating new TV show addictions, the most recent examples being The Walking Dead and Broad City.