The mophie card scanner adapter for iphone allows the user to access the headphone jack while scanning a credit cardhttp://www.mophie.com/Marketplace-iPhone-Mobile-Payment-Strip-Reader-p/1170_MP-IP4-BLK.htm
Photo: boundary by ank0ku http://www.flickr.com/photos/joshhr/4308535000/in/photostream/
The cardiio app detects the color change in your face when the heart beats. Simply place the phone in front of your face and it reads your heart beat. http://cardiio.com/https://www.youtube.com/watch?v=03NzgoQUe1UInstant heart rate, by azumio, detects heart rate by placing finger over camera http://www.azumio.com/apps/heart-rate/
Sleep Time uses the accelerometer as the phone is placed on the bed to determine movements and breathing to chart sleep cycles and provide feedback for better restinghttp://www.azumio.com/apps/sleep-time/
Isy uses the microphone to detect loud sounds. It compares the sound at different times to see if the sound is getting louder and will alert the user there is an alarm or siren nearby via vibrationhttps://play.google.com/store/apps/details?id=com.isyPhoto: siren by Nick Jones Everybody http://www.flickr.com/photos/nickjones/79838305/in/photostream/
DashCommand uses the iPhone as a display and for tuning a car’s engine. It connects to the car’s computer via an adapter.