Sensor output on an Arduino Nano to an iPhone headphone jack

Hi,

Background: I have a pressure sensor connected to an Arduino Nano that is generating a voltage that is being read by an application on my laptop via a com port and a USB cable.

I'd like to build an iOS app that reads that voltage via an iPhone headphone jack. The articles I've read talk about converting the voltage to a sound wave and having the app read the sound wave and convert that back to a voltage. This may be the best way but seems convoluted.

I'd rather not go with Bluetooth or Wi-Fi as it complicates what should be a simple process.

Can someone point me in a direction that might be useful?

Thank you, Ed

Ednewbie: I'd rather not go with Bluetooth or Wi-Fi as it complicates what should be a simple process.

But all this converting to sound and back is simple by comparison?

To the end user, it is easier to plug in a headset jack then figure out a Bluetooth or Wi-Fi connection.