This "app" is one of the best I have used so far. I am writing my Bachelor thesis and I am currently using a survey made from this website. It is very easy to monitor and very easy to make your questionnaire design. The best feature which I didn't find on other website is that you can insert pictures/images into your survey which is much appriciated. I am also required to use SPSS, and from my survey results I am capable of importing the results direct to SPSS which makes it much easier for!. I would recommend you to go ahead and try this.