Predictive text on iPhone is a small bar above the keyboard which shows word suggestions as you type. To disable and turn off predictive text on iPhone 6 and of course other iPhones, iPods and iPads running the latest iOS version, do as follows:
1. Open the Settings and go to the General settings,
2. Scroll down to the Keyboard settings and open it
3. Go down the menu and make sure the Predictive Text is toggled off. Now the suggestion bar must be gone.