Opera is experiencing massive growth on iOS and Android, thanks to the EU’s Digital Markets Act (DMA) that helped level the playing field.

The DMA targets “gatekeeper” companies, forcing them to play fair and not favor their own applications and services over those of rivals. As part of the DMA, iOS and Android must present a ballot screen to users, giving them the choice of default web browser.

It appears the option is paying off, with Opera reporting a 164% rise in new users on iOS between March 5 and March 7, the period when users first started seeing the ballot screen. In some markets that number was even higher, with France seeing a 402% increase.

“The day the ballot screen started to appear, we saw a spike in the growth of our daily active users, especially for Opera for iOS. We see this as indicative of two things: for one, the importance of regulation to provide a more level playing field, and for another, that users are hungry for new and innovative products that can deliver a superior online experience,” said Jørgen Arnesen, EVP Mobile at Opera.

In addition to giving users a prominent choice, the DMA also forced Apple to allow third-party browsers to use their own engines. Previously, Apple had forced all web browsers to use Safari’s WebKit engine. As a result, third-party browsers were little more than Safari skins—same engine, different interface.

The DMA appears to be paying off, giving users real choice and helping smaller developers better compete with their larger rivals.