Breaking into an apartment building in 30 seconds without a phone: Carry a brown paper (food delivery) bag. Stand by the intercom pretending to press buttons.

Breaking into an apartment building in 30 seconds without a phone: Carry a brown paper (food delivery) bag. Stand by the intercom pretending to press buttons. When someone comes in or out, tailgate behind them and say "thanks". 9 out of 10 times they'll even hold the door open for you.