Draft:Smartphone flashlight

Submission rejected on 8 December 2025 by Aydoh8 (talk).

This topic is not sufficiently notable for inclusion in Wikipedia.

Rejected by Aydoh8 17 days ago. Last edited by Darrylrose 16 days ago.

Comment: Struggle to see how a function on one model of smartphone is independently notable when literally every other phone does it as well. Aydo h8^{[what have I done now?]} 14:08, 8 December 2025 (UTC)

The smartphone flashlight (also known as a torch outside North America) is a built-in feature on modern smartphones that enables the device’s rear camera LED flash to operate as a continuous light source. Originally designed to assist photography in low-light conditions, the rear LED flash was later repurposed through software to provide general-purpose illumination.

The feature became widespread in the early 2010s as smartphones from multiple manufacturers—including Apple, Samsung, HTC, Nokia, LG and others—adopted rear-facing LED camera flashes. Today, flashlight functionality is considered a standard utility feature on both iOS and Android devices and is typically accessible from a quick-settings panel, lock screen shortcut, hardware gesture, or voice assistant.

Unlike the brief, high-intensity burst used for photography, flashlight mode operates at reduced sustained output to limit heat generation and battery drain. Smartphone manufacturers generally do not publish official luminous output specifications for flashlight operation.

History

Early camera flashes on mobile phones

Early mobile phones with cameras either lacked a flash entirely or relied on external xenon flash accessories. By the late 2000s, manufacturers began adopting compact white LED modules as permanent light sources for mobile photography due to their low power consumption, small size and suitability for continuous operation.

Introduction of continuous flashlight functionality

As LED camera flashes became more common, software developers enabled continuous illumination through third-party applications. This allowed smartphones to function as pocket flashlights, though early implementations often lacked efficient power management and system-level reliability.

System-level flashlight controls

By the early 2010s, major mobile operating systems integrated flashlight control directly into their system interfaces. On iOS, system-level flashlight access was introduced via Control Center in 2013. On Android, flashlight toggles became standard within the Quick Settings panel across multiple manufacturers and device models.

Brightness and beam control evolution

Subsequent generations of smartphone hardware introduced multi-level brightness control and more advanced multi-LED flash systems. Some premium smartphones now support segmented LED arrays that allow limited beam shaping during continuous flashlight operation.

Hardware implementation

Single-LED systems

Early smartphone flashlight systems relied on a single white LED mounted beside the rear camera. These provided limited illumination but established the foundation for continuous flashlight functionality.

Dual-LED (colour-matching) systems

Dual-LED systems combine white and amber LEDs to allow colour temperature matching for photography. In flashlight mode, these typically produce blended neutral illumination.

Multi-LED and segmented flash arrays

Modern premium smartphones use multi-LED flash modules or segmented LED arrays to improve illumination uniformity, sustained brightness and, in some designs, limited beam shaping through software control.

Software control

iOS implementation

On Apple’s iOS devices, flashlight access is available through Control Center, the Lock Screen shortcut, Siri voice commands, and automation via the Shortcuts app. Multiple brightness levels were introduced in iOS 10, initially via 3D Touch and later through long-press and Haptic Touch controls. On Pro-model iPhones equipped with segmented flash hardware, recent versions of iOS also allow limited beam width adjustment in flashlight mode.

Android implementation

On Android devices, flashlight control is typically accessed through the Quick Settings panel, lock screen gestures, or programmable hardware buttons. Many manufacturers, including Samsung, Google and Xiaomi, implement multi-level brightness control on supported devices. Some Android smartphones allow flashlight activation via double-pressing the power button, fingerprint sensor gestures, or voice assistant commands.

Brightness and luminosity

Smartphone manufacturers do not publish standardised lumen ratings for flashlight operation. Independent testing varies widely depending on measuring distance, thermal regulation, optical diffusion and software power limits. As a result, flashlight brightness is usually described comparatively rather than with fixed numerical values.

It is consistently observed that:

Early single-LED systems are dimmer than later generations
Multi-LED and segmented systems provide the brightest sustained flashlight output
Camera flash output is significantly brighter than continuous flashlight mode but cannot be sustained safely

Power consumption and thermal limits

Continuous flashlight operation generates significant heat due to sustained electrical load on the LED module. Most modern smartphones incorporate thermal throttling and automatic shut-off mechanisms to prevent overheating and reduce the risk of hardware damage or user injury.

Accessibility uses

Many smartphones allow the rear LED to be used as a visual alert for notifications, incoming calls and emergency warnings. This feature is commonly configured through accessibility settings and is widely used by hearing-impaired users.

Safety concerns

Prolonged exposure to high-intensity LEDs at close range may cause temporary visual discomfort or glare. Manufacturers generally caution against shining the flashlight directly into eyes at close distances. Extended flashlight use can also accelerate battery drain and contribute to device heating.

References

External links

Apple – iPhone Camera and Flash Technology
Android – Accessibility and flashlight documentation