In practice, that meant Snapchat had two sides. The left side of the app featured chats and stories shared with, or by, people’s friends. On the right side was content from publishers, amateur creators and celebrities and stories that Snap curated from user-generated videos and photos.

The goal was to expand the more lucrative media side of the business and to increase the app’s appeal to an older demographic. But over the past few months, the changes diluted the core chat experience, which became cluttered with user stories. Snapchat’s users, who are mostly young, quickly rebelled.

“Snap has their back against the wall,” said Daniel Ives, the head of technology research for GBH Insights. “They need to work with their user community.”

Now the company is moving stories made by friends back to the side of the app that also has media content. This change is aimed at decluttering the app’s chat function.

The pivots have some analysts worried about Mr. Spiegel’s leadership of Snap.

“What I’m looking for is some direction,” said Richard Greenfield, a media and technology analyst at BTIG. “Evan was so decisive in that your friends are distinct from influencers — you’re not friends with Kim Kardashian, so she shouldn’t be in your friends list — and yet now they seem to be wavering on that.”

Content, rather than chat, is “where the monetization potential is,” Mr. Greenfield added.

Anthony DiClemente, an analyst at Evercore ISI, said, “The app redesign is a question and an open debate.” He added, “I don’t know that the Snap leadership has proven itself to such a degree that you have high-conviction long-term investors in the stock right now.”