Final Fantasy: Brave Exvius, a free-to-play entry in the series made exclusively for iOS and Android devices, is available now. Combat follows classic turn-based conventions, and you hunt for items in dungeons while the game tells you a tale about a couple of knights, a young girl, and a crystal.
Since Final Fantasy: Brave Exvius is free to play, there are microtransactions. Most are cosmetic, so you can ignore them. If you want to fast-track your party, spring for the Early Bird Special, which contains everything you need to "grow [your] characters at a faster pace."