Assistive touch is one of the most used features of iOS which enables the iPhone and iPad owner have a virtual floating home button on the screen. To enable Assistive Touch on iPhone 6S and other iDevices running iOS 9.x, do as follows:
1. Open the Settings app
2. Tap to open the General settings
3. Scroll down to Accessibility and open it
4. Scroll down to Interaction settings and tap the Assistive Touch option
5. Now toggle the button to enable assistive touch on iPhone and iPad
6. You can also use the Customize Top Level Menu and Create New Gesture options to customize the assistive touch feature on your iOS device.