Pitched as an iPhone speakerphone and speaker alternative for marine use, Cobra's IPX7-rated submersible and floating handset HH500 ($170) looks like a walkie-talkie and packs a 1/3/6-Watt VHF radio, rechargeable battery pack, and other useful features. In addition to wirelessly pairing with Apple's devices, HH500 enables nautical users to tune into U.S.A., Canadian, and international channels, including all of the NOAA's weather channels,…