The ability for users to manually disable this throttling was introduced in iOS 11.3.

The iPhone (typically models 6, 6s, SE, 7, and 7 Plus) becomes noticeably slow, apps take a long time to load, and frame rates drop significantly. This is caused by Apple’s “Performance Management” software, which is automatically enabled after the device experiences an unexpected shutdown, due to the aged battery being unable to supply the necessary power during peak demand. The phone is throttling the CPU to prevent future shutdowns.

There are two primary solutions: The software workaround (Disabling the feature) and the permanent fix (Battery Replacement).

Option A: The Permanent Fix (Recommended)

Check Battery Health:

1. • Go to Settings Battery Battery Health & Charging (on older iOS versions, this may just be Battery Health).
   • Look at the Maximum Capacity percentage. If it is below 80%, the battery is considered degraded and should be replaced for optimal performance.

Replace the Battery:

1. • • Replacing the battery with a new one will restore the device’s ability to handle peak performance demandsOnce the battery health is restored, the performance management feature will automatically be turned off by the operating system, and the device will return to its original speed.
     • Option B: The Software Workaround (Use with Caution)

• Prerequisite: You must be running iOS 11.3 or a later version of iOS to access these settings.
• Warning: Disabling throttling significantly increases the risk of the phone experiencing unexpected shutdowns, especially in cold weather or during high-demand tasks (like gaming or intense browsing).

Navigate to Performance Settings:

1. • Go to Settings Battery Battery Health & Charging.

Locate “Peak Performance Capability”:

• In this section, if throttling is active, you will see a message similar to: “This iPhone has experienced an unexpected shutdown because the battery was unable to deliver the necessary peak power. Performance management has been applied to help prevent this from happening again.”
• Disable Throttling:
  • Next to this message, you will see a small blue link that says “Disable…”.
  • Tap the “Disable…” button.
  • Once you tap it, the performance management is turned off. The text will change to reflect that you have manually disabled the protection.

Note: Once you manually disable the feature, you cannot turn it back on manually. It will only be automatically re-enabled if the phone experiences another unexpected shutdown.