IPod the iPod Nano and Shuffle from its stores, marking the end of Apple producing standalone music players. Currently, the iPod Touch is the only iPod produced by Apple. The third-generation iPod had a weak bass response, as shown in audio tests. The combination of the undersized DC-blocking capacitors and the typical low impedance of most consumer headphones form a high-pass filter, which attenuates the low-frequency bass output. Similar capacitors were used in the fourth-generation iPods. The problem is reduced when using high-impedance headphones and is completely masked when driving high-impedance (line level) loads, such as an external headphone amplifier. The
People Power Company at Bitfone, which was acquired by Hewlett-Packard. People Power was initially envisioned as a greentech company with a focus on energy efficiency. In 2013, the company released its "Presence" app, which is designed to turn older smartphones and tablets into home monitoring devices and sensors using the device's built-in camera. The Presence app also allows users to monitor and control third-party internet-connected appliances and electrical usage in their homes. The app was originally available for iPad, iPhone, and iPod Touch devices. In mid-2013, the company's Chief Scientist, John Teeter, was selected as a Presidential Innovation Fellow and worked at the