Delphi and C++ Builder serial communication library for Prolific devices for Android.
uses Prolific PL2303 library
no special root access privileges needed
available for Delphi/C++ Builder XE6-XE7
source code included in full version
royalty free distribution in applications

Delphi serial communication library for FTDI devices for Android.

Features:

Uses FTDI D2XX library
No special root access privileges needed
Available for Delphi XE6-XE7
Source code included in full version
Royalty free distribution in applications

Delphi component for serial communication for OS X.

Features:

Communication with devices connected to serial port
Available for Delphi XE3 - XE7
Source code included in full version
Royalty free distribution in applications

Delphi component for serial communication for Android.

Delphi component for serial communication for OS X.

Features:

Communication with devices connected to serial port
Available for Delphi XE3 - XE7
Source code included in full version
Royalty free distribution in applications

Serial communication component for .NET.

communication with any device connected to serial port
easy of use and very powerful
uses multithreading and overlapping for maximum performance
available for .NET 2 - 4
source code included in full version
royalty free distribution in applications