Adrian Kingsley-Hughes/ZDNET Heat It Insect Bite Healer 4.0 / 5 Very good ZDNET's key takeaways The Heat It is available on Amazon for $30 for a limited time. It heats up from your smartphone and reduces swelling and itchiness from bug bites. While its power consumption is modest, it will take some charge from your phone. Follow ZDNET:  Add us as a preferred source  on Google. As someone who spends a lot of time outdoors (and someone who got hit with Lyme disease), it’s astonishing how often I forget to apply insect repellent. Just the other night, I spent the last half of a five-mile walk in a thick, annoying cloud of houseflies. Irritating, but at least they don’t bite. Not like horseflies… Now those things know how to bite! I’ve watched them land on my sleeve and start gnawing through the fabric.…