The Inbox by Gmail team confirmed that it is working on allowing predefined signatures and providing a delete button to Android Police's Artem Russakovskii on his Google+ post. Russakovskii was sharing why he had problems in getting along with Inbox by Gmail app, giving such as the missing 'mark an email unread' feature, labels, signatures, and no one-tap trash action. Inbox by Gmail replied on the post saying, "We're working on both Signatures and Delete."
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Apart from this, the team also commented about the missing 'mark as unread' feature, saying that the pin and snooze features in the mail management app were designed to replace it.
In April, Google updated its Inbox by Gmail app adding a new Web interface with the ability to set a custom Snooze time, and also added quick access to Contacts.
With the updated Inbox by Gmail, users were able to set custom morning, afternoon and evening Snooze times along with existing Snooze options from when the app was launched last year. The custom Snooze feature was highly requested by users since then.
It's worth mentioning that Microsoft has been lately revamping its Outlook.com email service alongside Outlook mobile app. Microsoft last month released the out-of-beta Outlook app for Android. The company after nearly four months of wait has now removed the preview tag from the app. Microsoft was recently also reported to be working on a Flow by Outlook, an Inbox by Gmail style lightweight email management app.