A device from Logitech can turn that new smartphone or tablet into a mobile speakerphone and teleconferencing system. The $169 Mobile Speakerphone P710e connects to mobile devices, as well as nonmobile ones, via USB, Bluetooth or NFC and delivers professional-grade audio through an omnidirectional mic with automatic gain, echo cancellation and noise reduction. There's also a headphone jack. If video is desired, the unit provides a stand for the mobile device and positions its camera at a natural angle. The pocket-sized P710e works with Linux, Mac OSX and Windows, is rated to deliver 15 hours between charges and can pair (via Bluetooth or NFC) with as many as eight devices. Charging can be done over USB or the included AC adapter.