Website and Companion App
One of the best features of FIFA Ultimate Team is that you are given the ability to manage your team when you’re away from your console. By going to the Ultimate Team web app you are able to do everything you can do on the console aside from play games.
Manage your current squads, create new ones, and use concept squads on the web. You can even place bids on players on the Transfer Market, as well as buy packs with Coins or FIFA Points. FIFA 15 Ultimate Team can follow you around wherever you go--for better or worse!
There is also a mobile app version available on the Google Play Store or iTunes called the EA SPORTS™ FIFA 15 Companion. Just like the web app, you can do anything you can do on the console (other than play games of course). This is great (although highly detrimental to your social life) if you are on the go and want to make that late-night Transfer List purchase.
An important note--you can only be signed into either the console game, web app, or mobile app. You cannot be signed into multiple ones at the same time.