The guest ID can simply be FIFA 19 Coins made utilizing a username but in the event that you ever delete the game and re install it, then you may lose all your progress so the Facebook ID is your way to go. It is unfortunate that the game doesn't offer you the choice to create a permanent account using password and username and more or less forces you to use Facebook login if you want to play seriously.
During login process, you could even create your character, which entails picking gender, skin color and hair, not one of which affect gameplay. Since you play the game and get points, you can purchase additional in-game items such as clothing and accessories for your character, which, again, don't impact gameplay and are only for aesthetics.
If you perform as duo or squad, the last team standing wins. In these two modes, it is possible to manually create your own team with usernames your friends or let the game automatically set you with random players.
After the game works pretty much exactly the FIFA Mobile Coins Buy same way as on other platforms. What's different is the control strategy. On the right are the controls to take, aim, jump, crouch, go prone, and reload. That sounds like a lot but you get used to it. What you do not quite get used to is the specific position of the keys on the screen and more often than not at the heat of the battle I found myself tapping empty subject of screen instead of the fire. Peeling away your eyes from the goal to look at the button often means the goal has now moved off. Mobile is the only platform where you need to consider before pressing the button, and that's exactly what makes it terrible for these games (yet, here we are).