Possible options for keeping my phone during US visa interview

Hi,

I will be coming to Chennai for the first time tomorrow for my US Visa appointment. They don't allow to carry your phones inside the embassy, not do they provide locker.

What are my possible options to keep my bag/phone safe during my interview.

I've heard that auto wala charges 2000 INR for keeping the phone. Is there any safe and cheap alternative than this?

Few more details - 1. I will be arriving early in the morning and will leave by evening. Hence don't have any hotel bookings. 2. I don't have any companion with me, hence can't give them to family members.