I have an alarm app that can be stopped only by turning off the phone. The problem is that I don't want this option ("to turn off the phone") because it's too tempting for me... So I was wondering if there's any app on Google Play that blocks the phone from turning off for a certain period of time.
No. As a protection against the OS going badly wrong and leaving the CPU running at full tilt until the battery runs down (or more likely, until the device overheats), you can always turn off the device by holding down the power button for several seconds. This isn't under the control of the OS, so there's no way an app can override it.
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