I'm so confused to choose a college for B.Tech and I'm interested in computers and mobile phones. Which branch should I take in engg.?

Try applying in NIT's. And, speaking about course. You can take Computer Science since you said that you are interested in Computers and mobiles. If you don't get CS course in NIT's and still wish to go with CSE you can go with some private institutes.

You can go for computer Science engineering as your interest is in computers. Refer this link, it will help you in taking a better decision. https://www.shiksha.com/careers.

Though, there are many different branches, according to your interest my suggestion for you will be to proceed with Computer Science Engineering. Here is the list of most popular engineering branches: Computer Science Engineering Electronics and Communication Engineering Electrical engineering Mech