Profile

Taken from the game's help section.

Your Profile
You can view your current status, as well as other player-specific information, via your Profile. You can also do things like check your inventory via the Item List, or peruse your collection in the Album. Messages sent from other players will also appear here.

Player Level
Your player level represents your overall strength in the game.

You primarily earn EXP to gain levels by completing quests. Once you have earned enough experience, your level will increase.

Leveling up may increase your AP, the number of people you can call for an assist, the number of teams in your battle deck, and even the cost cap of your battle deck. As an added reward, it will also instantly refill your AP and BP.

Player EXP can be viewed by tapping on the experience bar located on the top right of the home page. Use your level ups wisely!