A wireless transmitter device is configurable and operable to transfer energy to multiple receiver devices at the same time. The transmitter device is configured to enable one or more sections of a charging surface to transfer energy by selectively choosing one or more conductive traces in the transmitter device based on the position of the receiver device on the charging surface. The size and shape of each section of the charging surface that is used to transfer energy to a receiver device can change dynamically based on each receiver device. Additionally, the process of transferring energy to each receiver device may be adjusted during energy transfer based on conditions specific to each receiver device.