If by BCA add on courses, you mean to know, the BCA specialization course, then I am providing the name of the colleges in kerala which offers the course of BCA with specialization in Data Science, Cybersecurity & Forensic science, IoT etc-

Amrita School of Arts and Sciences, Amritapuri

Jawaharlal Nehru Institute of Arts and Science, Idukki

For colleges offering the course of BCA in kerala consider the link below:

https://university.careers360.com/colleges/list-of-bca-degree-colleges-in-kerala

For more information regarding BCA as a career consider the link below:

https://www.careers360.com/courses/bca-bachelor-of-computer-applications

I hope this helps. Wish you a great eve!