It's long enough to connect to the Positive and negitvie battery terminal on the battery. About 4" and 6" long. If you need to connect a grounding spot. i dont think it's long enough. Or you can connect it to your jumper cable if you have one. and that can extend the length.
yes I used mine to recharge my android and planned on using it when at fest as backup power as android tends to eat batteries, so I'd likewise plug my phone in when having a busy texting day so I could walk around with my phone. Be advised the recharge rate on this device is ALL night, it takes a while