Occasionally, an app on your iPhone may freeze up or otherwise malfunction. The iPhone’s reset functions will usually restore normal operation. A soft reset, called “restart” in the iPhone user manual, turns the device’s power completely off, halting all programs. Under certain circumstances, a troublesome app may prevent the iPhone from completing a soft reset. In that case, a hard reset is necessary. Writer Bio

Difference Between a Hard and Soft Reset on iPhone - 98