One of the great new features Apple added to the iOS 8 mail app is the ability for users to receive push notifications anytime a reply is added to a designated email thread. Users expecting an important email will undoubtedly find this feature useful as it allows them to remain in the loop without having to check their email incessantly.
To enable the feature, simply swipe to the left on a particular email and three buttons appear. Tap on the "More" button and the following menu presents itself.
Tap "Notify Me" and you'll then be prompted with a verification message indicating that you're on board with receiving a notification anytime someone replies to the specified email thread.
Upon doing so, any email with notification replies enabled will have a little bell icon located on the left.
A pretty simple, and yet useful, new feature.
As one would expect, disabling reply notifications for a specific email is just as easy. Simply access the "More" menu once again and select "Stop Notifying."