Snap has started rolling back Snapchat's wildly unpopular redesign, with iOS users receiving the update.

It puts friends' Snapchat Stories back on the same page as those from celebrities and shows snaps and chats in chronological order.

Research by YouGov found that millennials hated the new look.

Snap has begun rolling back Snapchat's controversial redesign, which research has found is wildly unpopular with millennials.

Snap announced in April that it would test changes to its redesign with a small group of users. The company confirmed this month that the changes would eventually roll out to everyone.

As of Thursday, iOS users were seeing the changes.

The updated design puts friends' Snapchat Stories and those from celebrities on the same page. Also, snaps and chats are once again in chronological order.

The redesigned Snapchat. Snapchat

When Snap announced its first-quarter earnings earlier this month, CEO Evan Spiegel called the redesign of the redesign an "optimizing" process "based on our ongoing experimentation and learning."

The changes coincided with new research from the polling company YouGov underlining the staggering unpopularity of the redesign, which Snap began rolling out late last year.

To get the app's impression score, YouGov asked consumers whether they had an overall positive or negative impression of Snapchat. That measure fell off a cliff among 18- to 34-year-olds in the US.

YouGov said Snapchat wiped out more than two years' worth of positive feelings among millennials in one swoop.

And they voted with their feet too. Snapchat's number of daily active users rose by just 2%, to 191 million, in the first three months of the year — the slowest sequential growth rate since Snap went public last year.

Analysts said the Snapchat redesign was a symptom of "a poorly structured company that is demonstrating a clear pattern of mismanagement."

Snap shares fell to a record low of $11.22 on May 2, the day after its earnings disaster, below its previous low of $11.28. They stood at $11.01 early Friday.