I wrote a blog post about this for iOS apps: https://dannysu.com/2015/12/11/best-ios-email-apps-for-privacy/ https://dannysu.com/2015/12/11/best-ios-email-apps-

I wrote a blog post about this for iOS apps: https://dannysu.com/2015/12/11/best-ios-email-apps-for-privacy/ https://dannysu.com/2015/12/11/best-ios-email-apps-for-priva... If you're on mobile, basically majority of the apps out there suck at this. You need to turn image loading off by default and then Gmail, built-in Mail, and FastMail are the only ones that pass.