Dr. Mario World allows you to link your Facebook and LINE accounts so you can connect with your friends through the game.
To do so, you need to beat stage 20. Then you’ll unlock the “Friends” option at the bottom of the screen. Tap the option and then tap “…” You’ll then be prompted to link your Facebook account by tapping the Facebook button and your LINE account by tapping the LINE button.
According to the in-game FAQs, once both you and your friends link your social media accounts, you will automatically become friends. You can also invite friends to join you in the game. Just tap the Friends button, tap “Add Friend” and then tap the Invite Friends button to get an invitation URL to send to your friend. Then the friend follows the instructions on how to send a friend request, which you can then accept from the Friend Requests menu.
Once you become friends, you can see your friends’ progress on the world map, compare your stars or battle points, send and ask for hearts and even battle against your friends.
Once you have linked your Facebook and/or LINE account, you cannot change the linked accounts according to the FAQs. You have to unlink the accounts and then link a new one. To do so, tap the Friends option, then tap “…” and then tap “Unlink LINE/Facebook Account.” When the confirmation screen appears, tap “OK.”
You can have up to 1,000 friends, according to the FAQs. You cannot remove a friend added through your social media account unless you unlink that account from the game. If you became friends via other means, you can simply remove them from the friend list.
To stop receiving notifications related to the game in the LINE app, open the app and go to the friends screen, then tap the gear icon, then go to Notifications, then tap Authorized apps, then tap the app settings and then turn Allow Messages or Allow Notifications to off.
For info on how to link your Nintendo Account, click here.