Are you frustrated by trying to figure out how to get started encrypting email with iOS Mail? It’s easy in macOS, but not so much so on the iPhone or iPad. I’ve dug into the process, consulted dozens of forum posts and support articles. Then I tested, retested, and tested my process again. As of iOS 10.2.1, the process I detail below should get you going with sending encrypted email under iOS, using Apple’s Mail app.
If you are interested in encrypted email in iOS, this is worth a read.