If you are using Sleep with the iPod touch, or if your iPhone or iPad is running iOS4, please be aware of the following considerations:

iPod touch

• The iPod touch does not have a proximity sensor, so placing your device face-down on the mattress during sleep recordings will not turn the display off.
  
• To conserve power, your iPod should be running iOS5 or later which will enable you to use the screen lock to background the application while recording sleep and activity data.
  
• The iPod touch does not contain a vibrate motor, so the Get Active Alerts will be issued via audible notifications only.

iOS4

• iOS 4 does not support access to the accelerometer sensor while the application is backgrounded, so Sleep by MotionX must be running in the foreground to collect sleep and/or step data. When recording sleep or a walk, the proximity sensor may be used to turn off the display to conserve power if you are using an iPhone.