First, let us address the elephant in the room… “Why does the smartphone audio suck when everything else seems to be awesome and smart?”
The simple answer is that the designs of iPhones and Android phones are optimized for on-screen performances, such as visual capacity, app operations, and browsing - but not for voice quality. That’s a result of size – while other electronic components have reduced in size over the years, microphone recording still requires large physical components. As a result, built-in microphones are tiny and operate with a very restricted frequency range.
Additionally, most of these built-in microphones support mono recording, but not stereo. The devices usually use low cut filters (AKA high pass filters) to suppress background noise – but that’s only good when you’re close to the sound that you want to record.
Newer models of iPhones and high-end Android phones are improving their sound recording abilities, but even so, the audio quality still can’t compete with external microphones when recording loud sounds, being used for in-field operations, etc.
If you’re a vlogger, a musician, or simply want to make great videos with your smartphone, you can’t cut corners with audio quality.
The good news is that there are plenty of external microphones available.