User Manual for GameSir G8 Galileo Mobile Gaming Controller

1. Setup

The GameSir G8 Galileo is designed for seamless plug-and-play functionality with most Android devices and the iPhone 15 series (USB-C). Its movable Type-C port ensures a reliable connection.

1.1 Device Compatibility

• Supported Devices: Most Android phones and iPhone 15 series (USB-C).
• Phone Size (without case): 110-185 mm in length.
• Phone Depth: 13 mm or below.
• Phone Camera Depth: ≤ 5mm.
• Case Compatibility: Recommended for use without a case or with cases within 1mm thickness. Thicker cases may prevent proper connection or charging.

To connect your device, gently extend the controller and align your phone's USB-C port with the controller's movable Type-C connector. Ensure a secure fit.

The GameSir G8 Galileo controller with a mobile phone securely inserted, ready for gaming.

The controller supports phones with thin silicon or clear cases, typically 1mm or less in thickness.

Universal fit design accommodates various phone sizes, with an extendable mechanism and spacious rear for camera bumps.

1.2 GameSir App (Android Only)

For Android users, the GameSir App provides additional customization options, including firmware updates, button remapping, and stick sensitivity adjustments. Please ensure you are using firmware version 129.55-1.4 for optimal performance.

The GameSir App is currently only available for Android devices and is not supported on iOS.

The GameSir App allows for full software customization of the controller, including button mappings and trigger sensitivity (Android only).

2. Operating Instructions

2.1 Core Features

• Hall Effect Joysticks/Triggers: Experience 360° seamless pinpoint control with Hall Effect sensing sticks, providing precision and durability. The analog triggers offer smooth and responsive input for a competitive edge.


Hall Effect technology ensures anti-drift performance and precise control for both joysticks and analog triggers.

• Pass-Through Charging & 3.5mm Audio Jack: Connect your phone's USB-C port to the controller for ultra-responsive gaming. The pass-through charging allows you to charge your phone while playing, and the integrated 3.5mm audio jack lets you use your favorite wired headphones.


Simultaneous pass-through charging and 3.5mm audio output for uninterrupted gaming sessions.

• Magnetic Detachable Faceplates: Customize the look of your G8 Galileo with magnetic detachable faceplates. The controller also includes 3 extra interchangeable thumbsticks (tall, small, dome) to suit your preference.


Easily swap faceplates and thumbsticks to personalize your controller and optimize comfort.

2.2 Button Functionality & Mapping

• On-the-fly Mappings: The G8 Galileo features 2 extra buttons that can be instantly programmed without software. Mappable buttons include A/B/X/Y/LB/RB/LT/RT/LS/RS/View/Menu/Capture/D-Pad.
• Multi-Function M Button: The 'M' button provides convenient control for various functions:
  • M + LT/RT: Toggle between hair trigger and linear trigger modes.
  • M + Button: Enable/Disable turbo function for specific buttons.
  • M + A: Switch between ABXY layout modes.

2.3 Supported Platforms & Games

The GameSir G8 Galileo supports a wide range of platforms and games:

• Platforms: Xbox, PlayStation, PC (via Steam Link, NVIDIA GeForce Now, Amazon Luna, Moonlight, Xbox Remote Play, Rainway).
• Supported Games: All controller-supported games such as Diablo Immortal, Minecraft, Fortnite, Genshin Impact, etc.

The controller supports a wide array of mobile games and cloud gaming platforms.

2.4 Indicator Status

• PS Mode: For iPhone 15 series and Android phones using PS Remote Play.
• G-Touch Mode: For Android phones playing touchscreen-only games (requires GameSir App to remap controls).
• Android Mode: For Android phones (Android users can only use PS Remote Play in PS mode; Android mode is not supported for PS Remote Play).

3. Maintenance

To ensure the longevity and optimal performance of your GameSir G8 Galileo controller, follow these maintenance guidelines:

• Cleaning: Use a soft, dry cloth to wipe down the controller regularly. Avoid using harsh chemicals or abrasive materials.
• Storage: Store the controller in a cool, dry place away from direct sunlight and extreme temperatures.
• Joystick Care: The Hall Effect joysticks are designed to be anti-drift and durable, requiring minimal maintenance. Avoid excessive force or twisting.
• Port Protection: Keep the Type-C port clean and free of debris. The movable design helps protect it during phone insertion and removal.

4. Troubleshooting

If you encounter any issues with your GameSir G8 Galileo, refer to the common problems and solutions below:

• Controller Not Connecting/Charging with Phone Case:

  The controller is designed for phones without a case or with very thin cases (1mm or less). Thicker cases may prevent the USB-C connector from fully engaging. Try removing your phone case or using a thinner one.
• GameSir App Issues (Crashing, Ads, UI Problems):

  The GameSir App is primarily for Android devices for advanced customization. Some users have reported UI issues or unexpected ads. If you experience crashes, try clearing the app's data or reinstalling it. Basic controller functions do not require the app.

• Accidental D-Pad Button Presses (Screenshot/Mode):

  The screenshot and mode buttons are located close to the D-pad. This can lead to accidental presses during intense gameplay. Exercise caution when using the D-pad, especially the 'down' direction, to avoid unintended actions.

• Controller Disconnecting Due to Auto-Sleep:

  The controller has an auto-sleep feature that may cause disconnections in some games. This feature is currently not user-configurable. If disconnections occur, restarting the game may resolve the issue.
• Joystick Drift:

  The GameSir G8 Galileo utilizes Hall Effect joysticks, which are designed to prevent stick drift. If you experience any drift, ensure the controller's firmware is up to date via the GameSir App (Android only).

5. Specifications

6. Warranty and Support

For detailed warranty information and direct customer support, please refer to the official GameSir website or contact their customer service directly.

An official User Manual (PDF) is also available for download:

Download User Manual (PDF)