Remode Manager for Android
Remode Manager is a particular Web Server that lets you send commands to your Android device . All commands are interpreted by Remode simple http API .
Among these controls are also APIs to read and write to a serial cable OTG .
It is full done with Delphi 10Seattle except for an Extrnal jar done in Java, to reuse some old code with some static functions.
For other info visit http://www.synaptica.info/prodotti/remode-developers/