A mobile device (1) for measuring at least one electrical biosignal. The device (1) comprises a first input (4) and a second input (5), a measuring circuit part (7) for providing an output signal indicating the electrical biosignal to be measured, the measuring circuit part (7) comprising a first input (8) and a second input (9), and a charging circuit part (13) for charging a rechargeable battery (3) inserted in the device (1), the charging circuit part (13) comprising a first input (14) and a second input (15). The first input (8) of the measuring circuit part (7) and the first input (14) of the charging circuit part (13) are connected to the first input (4) of the mobile device (1) and the second input (9) of the measuring circuit part (7) and the second input (15) of the charging circuit part (13) are connected to the second input (5) of the mobile device (1).
