If you like music, a streaming service like Pandora or Spotify on your cellphone will usually do the trick. You can watch streaming video and movies form Netflix. For good sound, check out the Logitech UE Mini Boom Box. It works via Bluetooth with your smartphone and tablet. The cost is about 89 bucks.
Another speaker system to consider when traveling is the Motorola Roadster Pro. This offers great hands-free, voice-powered phone use. It uses four built-in microphones with noise canceling for maximum clarity. The cost is 129 and it can work with two cellphones.
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