Handbook

LowLighter Guide

Everything you need to know to get the most out of LowLighter on macOS and Windows.

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Getting Started

LowLighter is an AI overlay that lives on top of your entire screen. Instead of copy-pasting text into ChatGPT or switching tabs, you press a hotkey, drag over anything visible, and get an instant answer right where you are.

1

Download & install

Grab the installer for macOS or Windows and run it. The app lives in your system tray / menu bar.
2

Create an account

Sign up with your email. You'll get 25 free Vision responses to try the full experience, no credit card required.
3

Set your hotkey

During onboarding, you'll choose a key combination (e.g. Ctrl+1). This becomes your trigger to summon LowLighter from anywhere.
4

Press the hotkey

Your screen dims slightly and a hint appears at the top. You're now in selection mode.
5

Drag over anything

Click and drag a rectangle around whatever you want analyzed: text, images, charts, code, UI elements, videos, anything visible on screen.
6

Get your answer

A floating overlay appears with the AI's response. It stays on top of everything until you dismiss it or press the hotkey again.

Modes

LowLighter has five modes that control how the AI processes your selection. You can switch modes from the home screen of the app, where each mode is shown as a card.

Answer

All Plans

The default mode. Sends your selection to the AI and returns a direct answer. Best for questions, problems, and general analysis.

Summarize

All Plans

Condenses long selections into concise summaries. Perfect for articles, documentation, emails, and dense content.

Translate

Basic & Pro

Translates the selected text into your chosen target language. You can change the target language from within the app. Supports 35+ languages including Chinese, Japanese, Korean, Arabic, Hindi, and all major European languages.

Explain

Pro Only

Breaks down complex content into a clear, step-by-step explanation. Great for code, math, diagrams, and technical material.

Rewrite

Pro Only

Rewrites the selected text in a cleaner, more polished way. Useful for improving drafts, emails, essays, or any written content.

Tip: You can click on any mode card on the home screen to enable or disable it. Disabled modes won't trigger when you press their hotkey, which is useful if you only use a few modes regularly.

Engine Modes

The engine determines how your selection is processed. You can change the engine in the settings page.

Auto

Default

Automatically analyzes your selection and routes to the best engine. If the content is pure text, it uses Fast (free). If it contains images, charts, or complex layouts, it uses Vision. This is the recommended setting for most users.

Fast (Text Only)

Uses OCR to extract text from your selection, then sends it to a text-based AI model. Faster and does not count toward your Vision limit. Works best with clean, readable text.

Vision (Accurate)

Sends a screenshot of your selection directly to a vision-capable AI model. Understands images, handwriting, diagrams, charts, code with syntax highlighting, and complex layouts. Each use counts toward your monthly Vision limit.

Note: Fast-engine responses are unlimited on all paid plans. Vision responses have a monthly limit (1,000 on Basic, 2,000 on Pro) that resets each billing cycle.

Hotkeys

Every mode has its own global hotkey. These work from anywhere on your computer, so you don't need to have LowLighter focused.

Mode	macOS Default	Windows Default
Answer	`Ctrl+1`	`Alt+1`
Summarize	`Ctrl+2`	`Alt+2`
Explain	`Ctrl+3`	`Alt+3`
Translate	`Ctrl+4`	`Alt+4`
Rewrite	`Ctrl+5`	`Alt+5`

Changing a hotkey: Click on the keycap display next to each mode in the settings page. The app will enter recording mode. Press your desired key combination, then release. Press Esc to cancel.

Conflict detection: If you try to assign a hotkey that's already used by another enabled mode, the app will warn you and reject the assignment. Hotkeys from locked modes (modes your plan doesn't include) are automatically freed up when you reassign them.

Overlay & Answer Box

The answer box is the floating panel that appears with the AI's response. It stays on top of all windows until you dismiss it.

Interacting with the answer

Right-click the answer box to copy the full response text to your clipboard.
Drag the answer box to reposition it anywhere on screen. The position is remembered.
Auto-sizing the answer box automatically adjusts its size based on the length and volume of the response text.
Press Escape or click outside the overlay to dismiss it.

Customization options

All of these are adjustable in the Overlay card on the settings page:

Transparency: Make the answer box semi-transparent so you can see content underneath.
Opacity: Control exactly how see-through the overlay is (0–100%).
Border: Show or hide the border around the answer box.
Fade effect: Smooth fade-in animation when the overlay appears.
Text color: Change the color of the answer text.
Fill color: Change the background color of the overlay.
Font size: Adjustable from the settings page. Make the answer text larger or smaller.
Font family: Choose from multiple fonts including Inter, monospace options, and more.

Selection Area

When you press your hotkey and start dragging, the selection area is the rectangle you draw on screen. You can customize how it looks and behaves.

Screen dim: Dims the rest of the screen while you're selecting, making it easier to see exactly what you're capturing. Adjustable opacity (0–100%).
Selection hint: Shows a small hint at the top of the screen when selection mode is active (e.g., "Drag to select"). Can be toggled off.
Border color: The color of the border around your selection rectangle. Default is gold.
Border transparency: Make the selection border semi-transparent.
Fill color & opacity: The subtle tint inside your selection rectangle. Fully adjustable color and opacity.

Phantom

LowLighter includes a suite of privacy features for users who want to keep their workflow discreet. Phantom Mode makes the app invisible on screen recordings, hides it from the dock/taskbar, and more.

Phantom Mode

Pro

The ultimate invisibility suite. When Phantom Mode is active, the entire app shifts to a purple theme to remind you it's on. Includes:

Content Protection hides LowLighter from screen recordings and screenshots using native OS-level protection.
Dock / Taskbar Hiding removes LowLighter from the Dock (macOS) or Taskbar (Windows) so it runs completely from the system tray.
Minimal Overlay provides faster, less detectable overlay animations with reduced visual footprint.

Trial users get 15 minutes of Phantom Mode to try it out.

Stealth Type

Pro

Instead of pasting the AI response from the clipboard, Stealth Type simulates individual keystrokes to type the answer character by character into the active text field. This means:

No clipboard history trace, so nothing is ever copied
Looks like you're naturally typing the response
Works with any text field, input box, or document editor

GhostKeys

Basic & Pro

Replaces standard global hotkeys with low-level keyboard hooks that are invisible to other applications. GhostKeys intercepts the keypress at the OS level so it stays private.

Aesthetics

Purely visual effects that run around the edges of your screen. These are optional and don't affect functionality. Available on Basic and Pro plans.

Ambient Frame

A glowing border effect around the edges of your entire screen. Configurable options:

Thickness: Width of the glow border (slider)
Strength: Intensity / blur of the glow effect
Multi-color Mode: Cascading rainbow gradient that transitions through colors
Single Color Mode: Use one solid color instead of the gradient
Pulsating: Gentle breathing animation effect

Winter Frame (Snowfall)

Falling snow particles along the edges of your screen. Configurable options:

Intensity: Number of snowflakes
Speed: How fast the snow falls
Size: Snowflake size
Color: Snow color (default white)
Glow: Soft glow effect on each snowflake
Wind: Horizontal drift effect

General Settings

Additional toggles available in the settings page.

Show in Menu Bar / System Tray: Keep the LowLighter icon visible in your menu bar (macOS) or system tray (Windows) for quick access.
Sound Feedback: Plays subtle sounds when you trigger a hotkey or receive an answer. On by default. Turn it off for silent operation.
Reduce Motion: Disables animations throughout the app for accessibility or if you prefer a more static interface.
Translation Language: Set the target language for Translate mode. Shown as a dropdown bar beneath the Translate mode card. Choose from 35+ supported languages.

Tips & Tricks

Right-click to copy

After the AI responds, right-click anywhere on the answer overlay to instantly copy the full response to your clipboard.

Disable modes you don't use

Click on any mode card on the home screen to toggle it off. This frees up the hotkey and prevents accidental triggers. You can re-enable it anytime.

Use Auto engine for best results

The Auto engine intelligently routes between Fast and Vision based on what you select. It saves your Vision responses for content that actually needs them.

Use Stealth Type for privacy

Enable Stealth Type to have the AI response typed out keystroke-by-keystroke instead of pasted, keeping your clipboard clean.

Select just what you need

Smaller, focused selections give better answers. Instead of selecting an entire page, drag over just the paragraph or image you need help with.

Make the overlay transparent

If you want to keep reading while the answer is visible, turn on overlay transparency and lower the opacity. The answer stays readable while the content behind it shows through.

Vision-heavy content? Consider Pro

If you frequently work with images, diagrams, or complex layouts, the Pro plan gives you 2,000 Vision responses per month (twice the Basic limit) along with Explain and Rewrite modes.

Check your usage from the Account page

The Account page in the app shows a usage graph of your Vision and Fast responses for the current billing period, plus stats like total requests, resets, and remaining Vision responses.

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