The application of the Information and Communication Technologies (ICTs) to the photovoltaic (PV) energy sector has increased notably in the last years. This paper presents a new mobile software application for maintenance tasks in PV installations by determining the PV output power of the system, the daily energy production, the clear-sky global solar radiation and other parameters associated with solar position from Global Position Data in handheld devices endowed with Android or Windows Mobile operating systems. The calculation of these parameters permits a technician to know if the PV plant is working properly, since the difference between the PV output power supplied by the installation in a clear-sky day for a determined hourly period and the values estimated by the application should be minimal. In case of fixed installations, the application also permits to determine if the PV module support structures of the installation are correctly oriented. Some comparisons between data supplied by four real PV installations and data calculated by the proposed application were performed for evaluation purposes. (C) 2011 Elsevier Ltd. All rights reserved.