In one embodiment, a mutual-capacitance sensing electrode array is disposed beneath a keyboard, and operates in conjunction with a series of single switches disposed beneath each of the keys in a keyboard. The electrode array and switches are employed in conjunction with one another to indicate that a letter, number or other symbol displayed on a particular key has been selected by a user. Although some embodiments find especially efficacious application in hand-held portable electronic devices such as mobile telephones, other embodiments are well suited for use in stationary equipment or other devices containing keyboards or control panels.