App communicates with S and 3 differently. S is complex, requires App to connect to Internet and car connected with internet. 3 uses Bluetooth, neither needs internet connection.Back before they redid the app last year it would hardly ever wake my S without having to kill the app and restart it. The new version is much better - even more so with my 3 - but still times out sometimes. I find if I kill the app and restart it always works the second time.