What is a common symptom of a failing battery in an iPhone?

A common symptom of a failing battery in an iPhone is that the device unexpectedly shuts down or does not hold a charge. As batteries age, their ability to hold a charge diminishes, leading to situations where the device may power off unexpectedly, even when there appears to be remaining battery percentage. This can be particularly concerning for users who depend on their devices for communication or essential tasks. In addition, failing batteries may not effectively provide the necessary power, causing the device to exhibit erratic behavior or struggles to maintain operation during usage.

The other options represent issues related to different components or conditions. A cracked and unresponsive screen pertains to physical damage, which is unrelated to battery performance. Running out of storage space speaks to the device's storage capacity management rather than functionality linked to the battery. Lastly, a camera failure may indicate software issues or hardware malfunctions specific to the camera module, again not related to the battery's condition.