Connect Arduino to Android using Rx - Tx instead of micro USB port

Hello,
I managed to create an Android app that communicates with an Arduino nano when plugged into the micro USB port
The setup is as followed :
Android -- OTG Cable (micro USB to USB) -- (USB to micro usb) -- Arduino nano

Unfortunately when I am doing the same on an other micro usb connector where I plugged Ground - 5V, Tx, and Rx, the Android app does NOT detect the connexion.

My question then is -> are the TX and Rx of the arduino the same as Data+ and Data- in usb ?

Thanks in advance for you help

Stan

PS: I am a mobile developer quite new to the world of Hardware and Arduino, please be indulgent :wink:

No.
The TX and RX pins are TTL serial.
These go into another chip on the board which does the TTL serial to USB protocol translation.
USB coms is a lot more complicated than a plain old RS-232 serial link.

Edit:
Google "Arduino FTDI USB to TTL Serial Adapter" if you need to convert TX RX pins to USB.

Thank you very much for your quick answer @pcbbc, I will look into it !
Stan