You can take part in exciting knock-out tournaments. It consists of 5 rounds in which 2 ships compete with each other and you have only 6 letters to combine and form words to make your ship move faster. Its simple but extremely addictive.
iPhone/iPad version (Universal - FREE):
https://itunes.apple.com/app/roll-a-word/id649806141?at=10l3Vy
Android version (Google play - FREE):
https://play.google.com/store/apps/details?id=com.ivanovichgames.rollaword
Android version (Amazon - FREE):
Amazon.com: Roll-a-Word: Appstore for Android
iPhone/iPad version (Universal - FREE):
https://itunes.apple.com/app/roll-a-word/id649806141?at=10l3Vy
Android version (Google play - FREE):
https://play.google.com/store/apps/details?id=com.ivanovichgames.rollaword
Android version (Amazon - FREE):
Amazon.com: Roll-a-Word: Appstore for Android