Apple has released the third public beta for iOS shortly after the third developer beta. That’s because the public betas are just the last developer beta, so public beta 3 is just developer beta 3 as public beta 2 was developer beta 3.
This means you can expect to see the same changes if you’re on the public beta channel. Apple doesn’t release an update log for these but users have reported fixes to GPS and CarPlay bugs along with other assorted bug fixes and performance updates.
Apple also released the third public beta for tvOS along side.
Both updates are now available for download so head over to the updates section of your device if they haven’t automatically downloaded it yet.
How To Download iOS 12 Beta Profile
you can simply download the profile by clicking on the download button and install the profile for the iOS 12 beta 3 or any Updated version of iOS 12.