The main problem with energy saving are short-living NAT session in the "carrier grade" NAT systems deployed by mobile ISPs. You need to ping the server aggres

The main problem with energy saving are short-living NAT session in the "carrier grade" NAT systems deployed by mobile ISPs. You need to ping the server aggressively to prevent a NAT timeout from killing your connection. On most networks, ping intervals of 15 minutes are sufficient, but some ISPs seem to be brain-dead enough to kill TCP connections even earlier, enforcing additional load on their own networks. However, it is hard to make a proper guessing algorithm to estimate the time between ping messages, so most apps hard-code it. yaxim is using 15mins and hoping for the best. Xabber is working with 1min (or 30s, not sure), Google's cloud connection is using a similarly low interval.