Read/write serial data over Wlan 802.11 between mobile (MIT APP) and RS232 Gateway

I don’t think so, unless you use a serial-network converter with the supported usb-serial chip or driver support for Android. But you can try my SerialOTG extension ver 1.2 that has support for byte oriented transmission over serial-otg adapters, BT and TCP, all using the same protocol. I have tested it with wlan connection from Android devices to TCP-terminal app, TCP-server app and used it for ModbusTCP communication.
You can follow the discussion in this thread:
https://community.appinventor.mit.edu/t/using-serial-with-ftdi/

The extension can be found at: