Hey Sintu !
For excelling in a career of Mobile App Development, it's advised one to go for CS. in a good Engg. College and thereafter continue with your interest in the career.
Mobile app development is one of the hottest career in the industry as of now and contains quite a many job prospects, you just need to proceed in the right path following :

1. Choose a major platform : Android, iOS, Windows etc.
2.Get the Required Training and Education. Getting a formal training and education in software development processes is indeed required.
3. Master your skills.
4. Practice your skills.
5. Apply for internships.

Hope this helps.

Good Luck !