iPhone 5 won't support simultaneous voice and data on Verizon or Sprint
Apple's new iPhone 5 features support for LTE networks across the world, but it won't be able to offer simultaneous voice and data on all of them. The Verge has confirmed with Verizon Wireless that the iPhone 5 …
Context & Ripple Effects
Apple's LTE-capable iPhone 5 lands after a long runway: the Wall Street Journal reported on September 7 that the new iPhone would support LTE around the world, capping three years in which Verizon positioned itself for the device following its 2009 preparations. The catch confirmed by The Verge is architectural, not optional: on Verizon and Sprint's CDMA networks, voice still rides the legacy circuit-switched layer, so the radio can't hold an LTE data session during a call.
The limitation traveled fast — NYT Bits, GigaOM, the San Francisco Chronicle, VentureBeat and others all picked up the story on launch day, making the missing capability a defining spec debate one day before September 14 pre-orders opened. On AT&T's GSM-based network, the same hardware juggles calls and data, which turns one phone into two very different user experiences depending on the carrier.
First-order effects
- Verizon and Sprint customers buying the iPhone 5 lose mobile data the moment they place or answer a call, unless they're on Wi-Fi — a regression against what those carriers' existing 3G smartphones could do.
- AT&T's GSM variant of the identical phone retains simultaneous voice and data, converting a hardware spec into a live carrier differentiator heading into the upgrade cycle.
Second-order effects
- AT&T gains a concrete marketing wedge against Verizon and Sprint at exactly the moment both rivals are spending heavily to win iPhone upgrades, forcing their sales pitches toward LTE speed instead of call-time usability.
- The gap puts pressure on Verizon and Sprint to move voice onto the packet network via VoLTE-style deployments, since the bottleneck is their legacy CDMA voice infrastructure rather than Apple's chipset.
Third-order effects
- If LTE becomes the default radio, the industry's path runs through all-IP voice: once carriers migrate calling off circuit-switched CDMA, the CDMA-versus-GSM feature split that separates these iPhone 5 variants disappears, and legacy voice networks become the constraint on flagship features rather than the handsets themselves.
The trend: The LTE transition is shifting the binding constraint on smartphone capabilities from handset silicon to carriers' legacy voice networks, pushing CDMA operators toward all-IP voice to stay competitive.