When I read an e-mail on my computer or another device the notification icon from the mail app goes away, but the lightflow email notification stays on.

This is a limitation in android 4.2 and below 3rd party apps don't have access to email data and can't monitor for the dismissal of a 3rd party apps notification icon.

We've teamed up with the developer of Aqua Mail to bring better functionality. This will allow clearing of notification read on other devices as well as separate configuration for each mailbox. It also has the benefit of swiping away notifications from the notification bar will clear correctly.

With android 4.3 upwards the Light Flow notification should disappear once viewed on another device.

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