The Lightning to 3.5mm headphone jack adapter bundled with iPhone 7
Given that iPhone's predecessor is iPod the digital music player, the listening experience is still a big part of the device for many people. So the removal of the 3.5mm headphone jack was bound to be controversial, despite the fact that Apple has provided many options to mitigate the inconvenience.
EarPods from iPhone 5 (left) and iPhone 7 (right), with the adapter at the far right
Primarily, the EarPod earphones bundled with iPhone 7 use Lightning connector, giving you at least one native solution. Along with that is a Lightning to 3.5mm headphone jack adapter that you can use with any other regular earphones and headphones. Because Lightning port is fully digital, the both the adapter and the earphones have DAC modules inside to provide analog audio output. Unless you must charge the phone at the same time, you're not worse off than before as long as the adapter works as intended.
On a side note, providing both a DAC-equipped earphone and an adapter resulted in sacrificing the plastic case for the earphones, likely because of costs. The case is now simply a throwaway paper packaging.