If your Pillow app does not detect and analyze sleep sessions unless you launch it manually please check the following:
Ensure Background App Refresh is enabled for Pillow:
Open the “Settings” app on your iPhone
Go to “General” → “Background App Refresh”
Scroll down to find “Pillow” and ensure the switch for “Pillow” is turned ON
Ensure that your iPhone is not in low battery mode
“Background app refresh” which is used by Pillow (see above) is controlled by iOS, your iPhone’s operating system. If your iPhone doesn’t have enough battery, iOS may choose not to run any apps that have requested to run in the background to save as much battery as possible.
Readjust Background App Refresh
Pillow uses “Background app refresh” in order to run in the background to detect and analyze your sleep. However, this process is controlled by iOS and it tries to be as efficient as possible by only allowing the apps that you are most likely to use at any given time during the day to run in the background. Sometimes this process needs to be readjusted. Our recommendation is to launch Pillow around the same time for 5-7 consecutive days to let iOS “learn” that behavior and re-adjust so that it runs Pillow in the background at the right time.
If the issue persists, please contact our support team to help you.