Normally, when you connect your headphone to your iOS device, it will start to output the audio from the headphone rather than the speaker and there's no way you can switch to the latter. AudioOut is a brand new jailbreak tweak that aims to save your day by fixing this issue.
Developed by vibez, AudioOut allows you to listen to a song from the device's external speaker even when the headphone is plugged in. Not only this, but the tweak also lets you control the audio from the headphone's controls such as its volume. This means that you can listen to a song from the device's external speaker and at the same time control the sound with the headphone's remote control.