After being virtually wiped out, pay phones in Kraków have made an inexplicable comeback. As such, many are new and actually work. Almost all of them require you use a phone card with an electronic chip, which can be obtained at most kiosks, but not all, so it may take some perseverance to track one down. The magic words are 'Proszę kartę telefoniczną.' These cards run down very fast if you are calling cell phones, so if you plan on making many such calls, get the biggest one you can find. Ring-a-ling.