I don't work at Dropbox but I've placed people there and coached candidates through their process. Here's what the recruiter phone screen actually is.
It's 30 minutes, usually with an in-house technical recruiter, sometimes with a sourcer who passed you to the team. The content breaks down roughly like this:
10-12 min: Background and motivation. They will ask why Dropbox specifically. "I want to work on storage at scale" is better than "great company, good compensation." Do your homework on what Dropbox's current engineering focus areas are, they've been talking publicly about the shift toward hybrid cloud and async collaboration tools. Show you know what the team actually works on.
10-12 min: Role fit. They'll ask about your current stack, team size, whether you've done on-call, and usually one light technical question to see if you're in the right ballpark. For senior roles this is often a short system design or architecture discussion, not a coding problem.
5 min: Logistics. Timeline, competing offers, location and remote preferences (they've been hybrid-flexible but check current policy). They will ask if you have competing offers, you should say yes even if it's just one process in flight. It's not bragging, it helps them move.
What I tell candidates: the phone screen is mostly a calibration and motivation check. If you clearly want this specific role and can articulate why, and you don't bomb the basics, you're probably through. The hard part comes later.
One thing that kills candidates here specifically: underselling scope. Dropbox operates at very large scale. If you worked on something impactful, say the numbers. "Our service handled X requests per day" > "a high-traffic service."