Actigraphy describes a method for monitoring human (and also animal) activities. The recorded activity patterns are used to determine phases of activity and phases of rest/sleep.

But probably the most important use of actigraphy can be found in sleep research. Its main purpose is to substitute or complement classical Polysomnography (PSG), since the required environment and devices are expensive.
The main purpose of PSG is to measure the different sleep stages during sleep.

Research around actigraphy as a substitute for PSG started in the late 70s and continues today, and research results have shown that actigraphy is suitable to analyse sleep patterns.

WakeApp’s unique sleep scoring algorithm is based on the latest findings from sleep research concerning actigraphy and was adapted for the iPhone.

Intelligent Wake-up Window

The orange area at the end of the movement graph above marks the 30 minute wake-up window. A movement must be strong enough to reach the orange area in order to trigger the alarm.
The wake-up window is calculated from previous movements and so adapts to your actual sleep pattern for that night.
The closer you get to the set alarm time, the smaller the required movement (always in relation to your prior movements during night). This ensures that the most suitable wake-up time is chosen within the wake-up window, while maximizing your sleep duration at the same time.