No, the app is not doing any activities in the background. You can even close the app and it will reappear on wakeup time. Of course the wakeup by light in the morning will consume some battery. We recommend to plug in the charging cable overnight so you can leave the house with a fully charged device.
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(Maybe not all changes are required. Try for yourself and report back please) Settings / Smart Manager / Auto-start Turn off Automatically […]
No. The night mode is optional. You can even close the app and it will reappear on wakeup time.
Phone settings / Apps / Battery / Gentle Wakeup Background restrictions must not be applied Battery must be not optimized Phone settings / […]
Yes, you can configure it in the app settings “General/Clock Information”. You can configure this separately for the nightstand clock in settings […]