The friend list is a list of the player's friends, accessible from a button in the top left of the profile page. In this menu, the player can see a vertical list of each of their added friends, each friend showing their Mii, a few Pikmin in their squad, their name, level, a handful of their badges, total steps, and the date that they were added as a friend.
There is a small postcard with a red ribbon around it in the bottom left of each friend's box, and tapping that allows the player to choose a postcard to send. A search bar exists on the top of the screen that can be used to search for a specific friend.
In the top left of the menu, there is a + symbol. Tapping this and confirming the pop-up at the bottom of the screen will bring the player to the adding friend menu. Shown here is a QR code and a 12-digit string of numbers which is the player's own friend code. This can be copied to the clipboard, shared, or refreshed. The refresh option produces a new friend code and QR code for the player.
Below this, there is a box labeled "Send a friend request:", with a text box below that. Entering or pasting a friend code and pressing "Send" will send a friend request to the player whose friend code was entered. Sending a nonexistent code will result in an error notifying the player that there is no such user. There is also a button to open the device's camera to scan another player's QR code.
Postcards can be sent between friends. To do this, the player must select the postcard icon of one of their friends, and then choose a postcard from their collection, then a Pikmin to send it with. Unlike expeditions, the Pikmin chosen will not have to cover the distance, but instead will travel instantly. It will return when the friend it was sent to has collected it in the garden.