I have this one, but I don't hugely recommend it. I mean, it works, It's a little finicky about positioning, and sometimes my phone seems to randomly stop charging. Although that could be my phone rather than the charger.

My mom has this one and loves it. It seems to work much better because of the triple-coil setup. A little pricier, but I'd say it's worth it.

I don't use a case, fwiw.