Portable electronic device with conversation management for incoming instant messages

A computer-implemented method, comprising:

• at a device with a touch screen display:
• while displaying a non-messaging application:
• receiving a first message from a first sender;
• in response to receiving the first message from the first sender, displaying, on the touch screen display, a notification that includes a representation of at least a portion of the first message that is overlaid on top of the non-messaging application, wherein the notification is different from a messaging application associated with the first message;
• in accordance with marking criteria being met for the first message, the marking criteria including a requirement that a user input interaction with the displayed representation of the at least a portion of the first message was detected on the touch screen display, marking the first message as read;
• and
• in accordance with the marking criteria not being met for the first message, forgoing marking the first message as read;
• and
• subsequent to displaying the representation of the at least a portion of the first message, displaying, on the touch screen display, the messaging application including:
• a plurality of representations of messages including representations of a plurality of messages including the first message, wherein one or more messages in the plurality of messages are marked as read and one or more messages in the plurality of messages are not marked as read, and wherein messages that have been marked as read are visually distinguished from messages that have not been marked as read in the plurality of representations of messages;
• and
• a selectable user interface element that, when selected, initiates a process for sending a message to one or more recipients other than the first sender, wherein the selectable user interface element is not included in the notification corresponding to the messaging application that is displayed overlaid on top of the non-messaging application.

A storage device storing one or more programs configured to be executed by one or more processors of an electronic device with a touch screen display, the one or more programs including instructions for:

• while displaying a non-messaging application:
• receiving a first message from a first sender;
• in response to receiving the first message from the first sender, displaying, on the touch screen display, a notification that includes a representation of at least a portion of the first message that is overlaid on top of the non-messaging application, wherein the notification is different from a messaging application associated with the first message;
• in accordance with marking criteria being met for the first message, the marking criteria including a requirement that a user input interaction with the displayed representation of the at least a portion of the first message was detected on the touch screen display, marking the first message as read;
• and
• in accordance with the marking criteria not being met for the first message, forgoing marking the first message as read;
• and
• subsequent to displaying the representation of the at least a portion of the first message, displaying, on the touch screen display, the messaging application including:
• a plurality of representations of messages including representations of a plurality of messages including the first message, wherein one or more messages in the plurality of messages are marked as read and one or more messages in the plurality of messages are not marked as read, and wherein messages that have been marked as read are visually distinguished from messages that have not been marked as read in the plurality of representations of messages;
• and
• a selectable user interface element that, when selected, initiates a process for sending a message to one or more recipients other than the first sender, wherein the selectable user interface element is not included in the notification corresponding to the messaging application that is displayed overlaid on top of the non-messaging application.