How Low Power Mode Affects ProMotion in iOS 18

Apple’s ProMotion technology delivers ultra-smooth visuals by dynamically scaling screen refresh rates up to 120Hz, but activating Low Power Mode in iOS 18 fundamentally alters this behavior. When enabled, Low Power Mode caps the maximum refresh rate at 60Hz and adjusts the adaptive scaling curve to prioritize energy conservation over fluid motion. This guide breaks down exactly how iOS 18 modifies ProMotion display refresh rates to extend battery life.

The 60Hz Maximum Frame Rate Cap

Under standard operating conditions, ProMotion on supported iPhone models (iPhone 13 Pro and newer Pro models) dynamically ramps up to 120Hz during fast scrolling, UI animations, and compatible gaming.

When Low Power Mode is activated in iOS 18, the system immediately cuts this maximum ceiling in half:

  • Standard Mode: Dynamic scaling between 1Hz/10Hz and 120Hz.
  • Low Power Mode: Dynamic scaling capped at a maximum of 60Hz.

By eliminating the 120Hz ceiling, the GPU and display driver consume significantly less power, as pushing 120 frames per second requires substantial processing overhead.

Adaptive Scaling at Lower Frequencies

Capping the refresh rate at 60Hz does not mean the display functions as a fixed 60Hz panel. In iOS 18, the ProMotion display engine retains its variable refresh rate capabilities beneath the 60Hz cap:

  • Static Content: When viewing still images, reading text, or leaving the screen idle, the display still ramps down to its lowest supported thresholds (down to 1Hz on iPhone 14 Pro, 15 Pro, and 16 Pro models; down to 10Hz on iPhone 13 Pro models).
  • Video Playback: Standard video formats, such as 24fps cinema content or 30fps video, continue to match their native frame rates to eliminate pull-down stutter and save power.
  • UI Interactions: Swiping and transitions are restricted to a maximum 60fps instead of 120fps.

Additional Display Reductions in iOS 18

In tandem with the refresh rate ceiling, Low Power Mode applies several related display modifications in iOS 18 to minimize battery draw:

  • Disabling Always-On Display: On compatible Pro devices, the Always-On lock screen is disabled completely, preventing the display from resting at 1Hz when locked.
  • Frame Pacing and GPU Throttling: System animations are tuned for lower render budgets, reducing overall GPU clocks and avoiding dropped frames within the 60Hz limit.
  • Brightness Adjustments: The operating system may reduce auto-brightness limits slightly under sustained load or low battery states.

To observe this behavior manually without enabling full system power restrictions, users can achieve a similar 60Hz cap by navigating to Settings > Accessibility > Motion and toggling on Limit Frame Rate. However, unlike Low Power Mode, this setting only caps the frame rate without disabling background activity, mail fetch, or the Always-On display.