After years of monotonous rumors and dashed hopes, Apple will apparently release a Verizon-compatible iPhone early next year, offering customers an alternative to its once-exclusive, much-maligned carrier AT&T. But the promise of improved service is already growing dimmer, some say, due to differences in the technology behind Verizon's and AT&T's cellular networks. Here are three ways the Verizon alternative may suffer from comparisons with current iPhones:

1. No multitasking
Apple likes to tout the way the AT&T iPhone lets users talk on the phone while checking email or browsing the internet at the same time. But "unless Verizon has a trick up its sleeve," customers won't be able to multitask on the new iPhone, says Beatweek Magazine, since Verizon's technology, known as CDMA, can't handle calls and data at the same time. The company "is working on providing that capability," Verizon executive Brian Higgins tells The Wall Street Journal, though he says only "fringe" users really consider it important. No way, counters an AT&T spokesperson: "When it comes to the smartphones, it's a big deal."

2. Decreased international capability
Verizon's technology "is widely used in the U.S., but less so elsewhere in the world," reports the WSJ, "so Verizon iPhone customers wouldn't be able to use their phones in many parts of Europe and Asia." Despite other complaints about its system, AT&T phones tend to have greater success overseas.

3. Shorter battery life
Another downside of CDMA is that it eats up battery life more quickly than AT&T's system, so Verizon iPhone users may be dealing more often with a dead phone at the end of the night. One upside: Until multitasking is an option on Verizon phones, the odds of maxing out their power supply may be lower.

Sources: Wall Street Journal, Beatweek Magazine