Global settings are account-independent settings. Most of them define how the user interface should look like.
The Display settings provide a lot of flexibility to control the global appearance of the app, as well as each of the main views, such as the account list, message lists and message display.
By default K-9 Mail will display the user interface in the language you're using for your Android system. With this setting you can override the system language, e.g. if your Android version doesn't support your native language but K-9 Mail does.
When using the dark theme messages can look wrong. This is why K-9 Mail allows you to override the app theme.
Enabling this setting will always use the theme configured in Message view theme below for the message view. Not using a fixed message theme means you can select a theme in the menu of the message view.
This setting specifies the theme that is used for the message view.
This setting specifies the theme that is used when composing a message.
Please see the wiki page Font size for details on font size settings.
Here you can configure whether or not K-9 Mail will use animations. Currently this is only affects the animation when switching from the message list to the message view and back.
This setting controls whether or not the account size is displayed in the list of accounts. Disabling it can speed up the display a bit.
Unchecking this will disable counting the number of unread and starred messages in the special accounts (Unified Inbox and All messages).
Here you can disable the special accounts Unified Inbox and All messages.
Note: As of K-9 Mail v4.802, third-party applications can only access information about messages in the Unified Inbox. So disabling this can lead to those apps no longer working properly.
When this setting is enabled folder names that are longer than can be displayed in one line in the folder list will be wrapped and displayed using multiple lines rather than being shortened with "..."
Here you can specify how many lines of preview of a message you want to see in the message list.
Note: If you set preview lines to 0 and disable contact pictures (see below) you get a special single line message list view.
With this you can disable the star icon that is used to indicate flagged messages.
Enable this to always show the checkboxes to select a message.
Disable this to display email addresses instead of correspondent names.
Show correspondent names above the subject line, rather than below it.
Show correspondent names from Contacts when available.
Here you can select the color to use for correspondent names from your Contacts. All other correspondents will be displayed in the default color.
Disable this if you don't want to display contact pictures (or place holder images) in the message list.
If this is checked the place holder images for correspondents with missing contact pictures or ones not in your Contacts will be displayed in different colors. If this is disabled the images will be displayed with a grey background.
Disabling this will display read and unread messages using the same background color in the message list. Then bold text in the first line is the only indicator that a message hasn't been read yet.
Threaded view is enabled by default and groups messages that belong to the same thread. Currently only messages in the same folder are grouped. Specifically, this will not include messages sent by you if those messages are not also stored in the current folder.
Please note that this is not the same as the conversation view you might know from e.g. Gmail.
This setting allows you to display the message list next to the message view. This is mainly useful for devices with a rather large screen, i.e. tablets.
When this is checked a fixed-width font will be used for plain text messages. The display of HTML messages is not influenced by this setting.
Configure which message actions will be promoted to the first level of the menu in the message view.
Note: Checking an item doesn't mean that this action will be displayed in the action bar. There is only a limited number of actions that will be displayed in the action bar, the rest will move to the so called overflow menu that is accessible using the icon with the three dots.
Enable this to shrink messages to fit the screen width.
When this setting is enabled K-9 Mail starts in the Unified Inbox.
Note: You shouldn't use this setting. Pressing the launcher icon when K-9 Mail has been started before will restore the app to its old state rather than starting it again. Put a "K-9 Accounts" shortcut on your home screen to always open the Unified Inbox.
Note: This setting isn't currently used and will be removed soon.
Here you can specify whether you want to use the hardware volume keys to move up and down in the message list, or move to the previous and next message in the message view.
When this setting is enabled deleting a message in the message view will return to the message list rather than moving to the previous/next message.
Enabling this setting always moves to the next message after deleting a message from the message view. When it is disabled you move to the next or previous message depending on your previous travel direction.
Here you can specify which actions should display a confirmation dialog.
You can enable confirmations for the following actions:
Only some options relating to notifications are shown here. Most of the settings for notifications are under Account Settings, which means you can choose different notification styles for each account.
You can set a Quiet Time to prevent notification from disturbing your sleep.
Here you can specify the time when notifications will be disabled.
This time specifies the end of the Quiet Time, when notifications will be enabled again.
K-9 Mail supports deleting messages directly from a notification (on Android 4.1 and newer).
The available settings are:
This setting specifies when K-9 Mail is allowed to synchronize messages in the background.
Available settings are:
An old Android version shipped with a faulty Gallery app that didn't show any selectable items. To work around this bug K-9 Mail adds the options "Add image" and "Add video" to the menu of the message composition screen when this setting is enabled.
Note: This setting should be automatically enabled when the faulty Gallery version is found on your device. Most users can ignore this setting and leave it unchecked.
Here you can specify a directory where your attachments are saved to when the "Save" button of an attachment is clicked. If a compatible file manager is installed (e.g. OI File Manager) you can simply select a directory. Otherwise you'll have to type in its name.
This setting allows you to hide the subject of a message in notifications.
Note: Currently, any value other than Never disables rich notifications (on Android versions that support them). This behavior will most likely change in the future to only disable the notification ticker that is visible from the lock screen.
Here you enable the logging of extra diagnostic information – e.g. if you're working with a developer to troubleshoot a problem. See the page on logging errors for more information.
Remember to disable debug logging once it's no longer required.
By default, sensitive information like passwords are not saved in the logs, but this option enables logging of sensitive information.