Apple s iPhones 6 models offer some new calling tricks, but they have the same old limitation on talking and surfing in some situations.
Just as is the case with older iPhones, the Sprint version of the new phones can t access the Internet over the carrier s network while users are on a call. The Verizon version has the same limitation when users phones are connected to its older, slower data network or haven t been configured to talk and surf on its newer, higher-speed one.
The limitation, which an Apple representative confirmed on Friday, is ironic given that the iPhone 6 models support advanced calling features including the ability to make calls over WiFi networks and to route calls over the carriers new, high-speed LTE networks.
Unlike many Android devices, Apple s iPhones have long suffered from the talk-and-surf limitation on cell networks based on CDMA technology, such as those operated by Sprint and Verizon. The shortcoming is due to the way those networks were designed — and Apple s refusal to design around their limitations.
The 3G CDMA networks didn t allow voice and data to be transmitted to one cellular antenna simultaneously. The antenna could be used for a voice call or a data transmission, but not both at the same time.
Some Android phone makers got around the problem by including a second CDMA cellular antenna in their devices. That allowed them to use one for making calls and the other for accessing the Internet. Apple chose not to go down that path.
Models made since the iPhone 5 support the 4G LTE networks that both Sprint and Verizon have been building to replace their older CDMA networks. But until recently, neither supported the ability to send voice calls over the LTE network. So, when an iPhone user would place a call, the phone would switch over to the 3G antenna and turn off access to the LTE radio.
(The versions of the iPhone made for AT&T, T-Mobile and other GSM networks worked similarly. When you made a call, the phone would switch over to the 3G radio. GSM s 3G technology supported simultaneous calling and data usage, but data access would be slower than if you were only surfing the Net over LTE.)
Fortunately, upgrades to the cellular networks and Apple s phones may make this limitation finally disappear. Over the last year, all the U.S. major carriers but Sprint have started to roll out support for Voice over LTE (or VoLTE), a new standard for placing calls over the new LTE networks. Unlike their predecessors, the new iPhone 6 models support VoLTE.
On Verizon, if you use the iPhone 6 to make a VoLTE call — a feature dubbed by the company Advanced Calling 1.0 — you ll be able to surf the Internet at the same time, said company spokeswoman Heidi Flato. If you make a VoLTE call on T-Mobile or AT&T, you should be able to continue to surf the Net over their high-speed LTE networks. T-Mobile also promises to seamlessly transfer calls placed over a WiFi network to its VoLTE system when a user roams beyond the range of the WiFi router.
Sprint has yet to say when it plans to roll out VoLTE. And even on Verizon there are limitations to the new technology. Users have to manually configure their phones to use the VoLTE network. And if they happen to move between a cellular tower that supports VoLTE to one that doesn t, they can expect to have their calls drop, Flato said.
To be sure the limitation on talking and surfing has never been absolute, even for the CDMA iPhones. Both new and old iPhones for Sprint and Verzion supported simultaneous calling and surfing if the phones were connected to a WiFi network. Users could also surf the Internet if they placed calls over third-party apps such as Skype, rather than using the built-in dialers.
Photo: Apple CEO Tim Cook unveiling the new iPhone 6 models earlier this month (Justin Sullivan/Getty Images).
