Auto BT Fallback for Carplay

Does your Android head unit scan for CarPlay across all paired Bluetooth devices and always end up connecting to the wrong one? BTManager fixes that automatically.

**What is BTManager for?**

Many Android head units implement wireless CarPlay by scanning indiscriminately through all previously paired Bluetooth devices. When more than one iPhone is paired, or when both phones and tablets share the same bonded device list, the head unit may connect to the wrong device, fail the CarPlay session, or simply get stuck waiting.

BTManager acts as an active Bluetooth manager that, in Fallback mode, automatically cycles through your selected devices —in the order you configure— until one of them establishes a connection. If a device does not respond within the configured timeout, it moves on to the next one, looping continuously until the desired connection is made.

**Operating modes**

• **Manual mode** — View all paired Bluetooth devices and connect or disconnect any of them with a single tap. Full direct control.

• **Fallback mode** — The app automatically cycles through the selected devices in priority order. For each device it waits a configurable amount of time (10, 20, or 30 seconds). If no connection is established, it moves to the next one. The cycle repeats until one device connects.

**Key features**

• Real connection state detection using Bluetooth A2DP and HFP/Headset profiles.

• Automatic prioritization: the device that most recently connected successfully is tried first in the next cycle.

• Configurable per-device timeout: 10, 20, or 30 seconds.

• Device selection for Fallback mode: choose exactly which devices participate in the automatic rotation.

• iPhone / CarPlay support: 15-second grace window to avoid false disconnection states during CarPlay negotiation.

• Interface optimized for Android head units with landscape screens.

• Configurable language: Spanish and English.

• Configurable screen orientation: landscape, portrait, or automatic.

• No ads, no tracking, no network permissions.

**Required permissions**

The app only requests the Bluetooth permissions, strictly necessary to detect and manage paired devices. No internet access required.

**Requirements**

• Android 12 or higher

• Bluetooth enabled

• Previously paired (bonded) devices