-- Twitter, instant messaging, and push notification services, which have to constantly keep a network pipe open for incoming messages, don't mesh well with NAT, Ladid said. The applications have to keep telling the carrier that the temporary IP address is still in use. Sending those "keep alive" packets back and forth consumes battery life and network capacity, Ladid said.
An IPv6 address could stay with the phone, so none of those checks would be required.
"Since these devices do not have a constant IP address ... this NAT address has always, every 30 seconds, to say, 'I'm still on' to justify its presence," Ladid said. With IPv6, the phone could have its own unique Internet address and avoid that administrative traffic.
-- Connected-home devices such as security cameras and networked appliances with IPv6 can exchange data directly with another device across the Internet, such as the homeowner's smartphone. That gives more flexibility in how consumers can use those devices. For example, a smartphone can stream video from a home surveillance camera natively, without a special service, Ericsson's Garneij said. Also, getting a new Internet-connected device online for the first time can be easier when the manufacturer can assign it a permanent IPv6 address, Garneij said.
-- With a static address, it's easier to keep a data session alive while a smartphone or tablet travels with the user from one cell to another, Geesey said. Carriers do a pretty good job today of handing off regular voice calls between cell towers, using techniques that have been perfected over years of development. But mobile data handoffs can be more complicated, as devices move between 3G and 4G and application sessions have to be maintained.
An IPv6 address can remain constant and keep those sessions going, Geesey said. And in the next few years, when carriers turn their voice calls into data sessions using voice over LTE, this use of IPv6 is likely to grow more important, he said.
Stephen Lawson covers mobile, storage and networking technologies for The IDG News Service. Follow Stephen on Twitter at @sdlawsonmedia. Stephen's e-mail address is stephen_lawson@idg.com