How do I move/take action on multiple messages in the list?

Onmail provides the ability to select multiple messages, and then and apply an action to those messages at once. Multi-select options include mark as done, mark as read/unread, move to trash, mark as spam, add to label, and permanently delete (bypassing the trash.)

Instructions for enabling multi-select are as follows:

Desktop:

1. From the messages list, tap the small circle to the left of the sender's avatar
2. From here, select all messages you wish to take action on (or tap "select all" to select all messages in the list.)

iOS/Android:

1. From the messages list, tap (and hold) any message and enable multi-select
2. Select all messages you wish to take action on (or tap the dot above the action bar to select all messages.)