Is “app” word universal enough for use in academic writing?

While writing thesis, you have to be very careful that you should not use any type of informal language. The thesis should be drafted in a completely formal tone. Now talking about apps- the term is recognized and widely used as a short form. I am not so sure, whether or not, the term apps is an abbreviation or a short form but whatever it is you should define it first in the introduction part that the term ‘application’ and ‘apps’ are synonymous. I also had a thesis in mobile computing in my final year of post graduation in computer science and there I did a blunder by not defining the same term apps as application for which I was severely indicted by my professor, which is why I say to you to use the term apps only after defining it in the introductory phase.

I really hope the information is of worth.