My computer and android phone use same home wireless network. When I receive a call to my Skype Online number, the computer starts ringing immediately but the smartphone rings only after 5 or 6 more rings. If I turn the Android off and on, it rings on the first ring but, thereafter, on the 5th or 6th ring. I've reinstalled many times with same results.
If I turn off skyp on my computer, incoming calls USUALLY go straight to voicemail, even though my android is on. It's almost like skype can't unsleep my android. But the android always rings if I hit any button (unsleeping it).
Many times, with the computer off, I've let incoming calls ring 4 times and then hang up (I"m making the test call on a landline). On occassion, I've called another unrelated number on the landline and the android rings one time....30 seconds after I hung up!
On the other hand, I always receive notifications of missed calls which shouldn't have occured because my android was on and in my pocket. Unfortunately, the missed calls were important business calls and clearly skype "can't be trusted" on my android.
I've made many different tests, e.g., computer on, off, android on, in sleep, and any combination I can think of. Sometimes the android works; most the time it doesn't. It just makes no sense.
One thing does seem consistent: If the android screen is lit (not in sleep [I'm not sure sleep is the correct term]), it always works.