Final Fantasy XIV Companion is the official application for players of Final Fantasy XIV. This app allows players to chat with friends, manage schedules, and handle items and market transactions from their smartphones. To use this app, players must have a Square Enix account and have already agreed to the service contract for the Final Fantasy XIV product. If the game’s usage period has expired, some functions, such as chat, are still available for 30 days. After 31 days, all features are no longer available.

One of the app's main features is chat. Players can chat with friends, free companies, and linkshell members who are also using the Final Fantasy XIV Companion app. Another feature is the scheduler, which allows players to manage their schedules and coordinate with friends, free companies, and linkshell members. Additionally, players can check the items they own, move items around, and dispose of unnecessary items through the app. They can also use the app's currency (Kupo nuts and Mog coins) to buy and sell items on the market.