Because hearing aid technology changes rapidly over time, the technology used by children today will evolve and be replaced with more advanced technology in a few short years. For example, Bluetooth connectivity currently enables users to link their hearing aids wirelessly to personal digital devices (e.g., cellular phone, computer, tablet), a feature that was introduced recently and that may be replaced by a new form of connectively just as quickly. Likewise, signal processing strategies that optimize the amplification bandwidth and listening in noise will continue to evolve, requiring careful attention to appropriate real-ear and behavioral measures to determine benefit.