I initially bought the cheapest Bluetooth adapter on Ebay I could find. It looked like this:This adapter soon started to have problems connecting to my Android phone or tablet, and would only connect one out of ten time. So, I went and bought a new Bluetooth adapter off of Ebay that looks like this: and now my tablet and phone connect instantly. However, my iPhone 4s NEVER connected to either of them. It never even found them when searching for Bluetooth devices. So, my two questions are this: why won't the iPhone connect to these Bluetooth adapters, and will leaving them plugged in all the time be bad for them? (I am wondering if this is why my first adapter doesn't want to work properly anymore)?