We do not recommend using Sleep Cycle without a charger connected. Sleep Cycle uses at average 30% of the battery during one night, sometimes more sometimes less. If you do not charge your device during the night it risks running out of battery before the morning. You can activate battery warning under the tab ‘Settings’ to enable Sleep Cycle to warn you if you’re running out of battery, but we still recommend setting a back-up alarm if you wish to sleep without the charger connected.
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