public class TouchKeyboardExample : Monobehaviour {

    private TouchScreenKeyboard touchScreenKeyboard;
    private string inputText = string.Empty;

    void Start () {
        touchScreenKeyboard = TouchScreenKeyboard.Open(inputText, TouchScreenKeyboardType.Default);
    }

    void Update () {
        if(touchScreenKeyboard == null)
            return;
        inputText = touchScreenKeyboard.text;
        if(touchScreenKeyboard.done)
            Debug.Log("User typed in "+inputText);
        if(touchScreenKeyboard.wasCanceled)
            Debug.Log("User canceled input");
    }

}