The huge, headline-grabbing news out of Uber this week was the resignation of its chief executive, Travis Kalanick, under pressure from the company’s board, a stunning move that capped a monthslong crisis involving sexual harassment, executive misbehavior and Uber’s hard-nosed culture.

But amid the drama leading up to Mr. Kalanick’s forced departure, Uber made a quieter change that could represent another momentous shift for the company. On Tuesday, the company announced that passengers would soon be able to tip their drivers through the Uber app.

The change, which Uber plans to roll out nationwide next month, is a sudden reversal of longstanding company policy, and a move Uber fiercely resisted for years.

Under Mr. Kalanick, the company argued that giving riders the ability to tip drivers would create “friction” in an otherwise seamless transaction and lead to awkward interactions between riders and drivers. The company even cited a 2008 Cornell University study that found that consumers tipped black employees less generously than white employees, and suggested that adding in-app tipping would lead to racial discrimination.