Methods and apparatuses to adjust isolation between I/O ports. An apparatus includes a die, a first input or output (I/O) port, a second I/O port, and a third I/O port. The second I/O port is between the first I/O port and the third I/O port. A variable capacitor is electrically connected to the second I/O port and is configurable to adjust isolation between the first I/O port and the third I/O port. A method includes performing, by a die, a first RF function via a first I/O port; tuning a variable capacitor electrically connected to a second I/O port to adjust isolation between the first I/O port and a third I/O port, the second I/O port being between the first I/O port and the third I/O port; and performing, by the die, a second RF function via a third I/O port.