If you’re like most people, you probably check your email on your phone while you’re on the go. But if you want to confirm an email on Instagram, sometimes your phone won’t let you open the app. Here’s how to do it on an iPhone or Android device. iPhone: Open the Mail app and tap the message that you want to confirm. Tap the “Open in” button next to “Mail.” If the email is an attachment, tap “Open attachment” and then tap “Confirm.” Android: Open your email app and tap the message that you want to confirm. Tap the three lines in the top left corner of the message (or long press it if it’s a picture). Tap “Open in” and then tap “Mail.” If the email is an attachment, tap “Open attachment” and then tap “Confirm.” ..