skype on android is really, really bad. it doesn't even bother to tell you if your wifi is turned off. it'll just "ring ring ring ring" then show a message that the person wasn't available.
I use their subscriptions plan to call home from my Nexus 4. Most of the time skype on android shows offline users as online. Sometimes it shows me that I am signed in and online, but nobody could see me till I try to signout and signin multiple times. The worst problem is it reboots the phone frequently whenever i do video calls. Gets updates often, but they never fixed any of these problems.
Worse than that; I've found Skype on Android will actually kill the wifi connection. It's awful.