I applied through university. The process took 2 days. I interviewed at Headstrong
Interview
First Round: Aptitude + English Comprehension. Not too tough. Around 150 students appeared and 90 cleared first round
Second Round: Group Discussion. Genera Topic. 40 cleared this round
Third Round: Technical + HR interview. They basically ask you about your projects and few puzzles. 18 students were finally selected.
Selection in successive round is done by cumulating marks of previous round