A shaving apparatus comprising: a main housing accommodating a motor and a driving output member coupled to the motor; a shaving unit comprising a first shaving unit portion and a second shaving unit portion, wherein: - the first shaving unit portion is connected to the main housing in a stationary position relative to the main housing and accommodates a single driven input member which is connected to the driving output member and rotatable about an axis of rotation; and - the second shaving unit portion comprises a support structure, at least one hair-cutting unit supported by the support structure, and a drive unit connected to the single driven input member and to the hair-cutting unit, wherein the hair-cutting unit comprises an external cutting member with hair-entry apertures and an internal cutting member which is movable relative to the external cutting member, and wherein the drive unit is arranged to transmit a driving force from the single driven input member to the internal cutting member; and an adjustment system configured to adjust an operational parameter of the shaving apparatus; characterized in that: the first and the second shaving unit portions (7; 8) are mutually connected by means of a connection mechanism (26, 27) which is configured to allow manual rotation of the second shaving unit portion relative to the first shaving unit portion about a rotational axis coinciding with the axis of rotation of the single driven input member; the adjustment system comprises a sensing unit which is configured to have an output property which varies in dependence on an angular position of the second shaving unit portion relative to the first shaving unit portion about the rotational axis; and the adjustment system is configured to adjust the operational parameter in dependence on the output property of the sensing unit. a main housing accommodating a motor and a driving output member coupled to the motor; a shaving unit comprising a first shaving unit portion and a second shaving unit portion, wherein: - the first shaving unit portion is connected to the main housing in a stationary position relative to the main housing and accommodates a single driven input member which is connected to the driving output member and rotatable about an axis of rotation; and - the second shaving unit portion comprises a support structure, at least one hair-cutting unit supported by the support structure, and a drive unit connected to the single driven input member and to the hair-cutting unit, wherein the hair-cutting unit comprises an external cutting member with hair-entry apertures and an internal cutting member which is movable relative to the external cutting member, and wherein the drive unit is arranged to transmit a driving force from the single driven input member to the internal cutting member; and - the first shaving unit portion is connected to the main housing in a stationary position relative to the main housing and accommodates a single driven input member which is connected to the driving output member and rotatable about an axis of rotation; and - the second shaving unit portion comprises a support structure, at least one hair-cutting unit supported by the support structure, and a drive unit connected to the single driven input member and to the hair-cutting unit, wherein the hair-cutting unit comprises an external cutting member with hair-entry apertures and an internal cutting member which is movable relative to the external cutting member, and wherein the drive unit is arranged to transmit a driving force from the single driven input member to the internal cutting member; and an adjustment system configured to adjust an operational parameter of the shaving apparatus; characterized in that: the first and the second shaving unit portions (7; 8) are mutually connected by means of a connection mechanism (26, 27) which is configured to allow manual rotation of the second shaving unit portion relative to the first shaving unit portion about a rotational axis coinciding with the axis of rotation of the single driven input member; the adjustment system comprises a sensing unit which is configured to have an output property which varies in dependence on an angular position of the second shaving unit portion relative to the first shaving unit portion about the rotational axis; and the adjustment system is configured to adjust the operational parameter in dependence on the output property of the sensing unit. the first and the second shaving unit portions (7; 8) are mutually connected by means of a connection mechanism (26, 27) which is configured to allow manual rotation of the second shaving unit portion relative to the first shaving unit portion about a rotational axis coinciding with the axis of rotation of the single driven input member; the adjustment system comprises a sensing unit which is configured to have an output property which varies in dependence on an angular position of the second shaving unit portion relative to the first shaving unit portion about the rotational axis; and the adjustment system is configured to adjust the operational parameter in dependence on the output property of the sensing unit.