Bought just before Christmas. I gave them away and kept one for myself. So far none of them have had any problems. I have mine attached to my keys and it is very helpful. To do this, you need some kind of connector. I've used it most in my car with a USB charger. It looks cute and is way better than carrying around a string every day. I don't use it every day, mostly when I'm not at home and my phone will soon run out of power. So far it has been very reliable. I will update this review if anything changes. These are great gifts too!