ClientBridgeX: TCP USB Serial

ClientBridgeX turns an Android phone or tablet into a bridge between a TCP server and a USB serial device. Data flows both ways: what the server sends reaches the serial port, and what the device answers goes back over the network.

The app is the client side of that link. It dials out to the host and port you configure and never listens for incoming connections, so it works from any network that can reach your server, mobile data included.

MANY TO MANY, NOT ONE TO ONE
Stay connected to several servers at once and keep several USB devices open at the same time. Each device carries its own list of allowed servers, so you decide which connection reaches which piece of hardware instead of broadcasting everything everywhere.

SERIAL CONFIGURATION
Baud rate from 300 to 115200. Data bits 5 to 8. Parity none, even, odd, mark or space. Stop bits 1, 1.5 or 2. Settings are saved per device by vendor, product and port, so hardware you plug in again comes back configured.

WHERE ONE MESSAGE ENDS
Serial data arrives in fragments with no framing of its own. Tell the app the size you expect a message to be, and it works out the grouping window from that size at the current baud rate, closing a message on an idle gap. Frames reach the log grouped the way the device actually sent them.

TWO VIEWS OF THE TRAFFIC
Summary shows the exchange grouped message by message. Terminal shows the raw stream line by line. Each switches independently between ASCII and hexadecimal, with its own text size and scrollback depth.

SENDING DATA
Type in ASCII, or use the built-in hexadecimal keyboard. Choose which server the message goes to, and which line ending is appended to it.

LOGS
Summary and Terminal each keep their own log, written as .txt or .csv. Share either one through the Android share sheet, to wherever you want it.

BUILT TO STAY UP
The bridge runs as a foreground service and holds the locks it needs to keep working with the screen off. Servers you mark for auto-connect come back on their own, and if the device restarts the session is restored.

PRIVACY
No account, no analytics, no advertising, no trackers. Nothing you configure or transmit reaches the developer — the app has no servers of its own. Full policy: https://sites.google.com/view/clientbridgex-privacy-policy/inicio?authuser=1

REQUIREMENTS
Android 8.0 or later, and a device with USB host support (OTG).