A number of changes could include allowing users to replace preinstalled apps, namely Safari or Mail, with third-party options of their choosing, according to Bloomberg.
The Cupertino, Calif., company could also loosen restrictions on third-party music rival Spotify and open its HomePod speaker to third-party music-streaming services.
Apple currently installs 38 default apps, Bloomberg reported. They include the Safari web browser, Maps, Messages, Mail and others.
Developers have long complained that Apple's closed system unfairly freezes them out.
In addition to the restrictions in Apple's operating system, the company takes a 30% cut of subscriptions made within the App Store.
Netflix (NFLX) - Get Report, Spotify (SPOT) - Get Report and Alphabet's (GOOGL) - Get Report YouTube have distanced themselves from Apple's App Store fees by directing users to sign up on their own sites.
Last year, Spotify filed an antitrust complaint in the EU, arguing that Apple unfairly squeezes rivals by charging fees and locking them out of certain platforms, such as HomePod.
Apple's App Store practices are also the subject of an antitrust probe in the U.S., with the Department of Justice reportedly questioning developers over their dealings with Apple.
If Apple introduces any changes to how third-party apps work on its operating systems, investors and others may hear more at its annual WWDC developer conference, which is typically held in June.
Apple shares at last check were trading 1.2% lower at $319.91.