Tesla crash with no one driving leaves 2 dead NASA's Mars helicopter Peloton Tread Plus warning Marvel's Shang-Chi trailer Apple's April 20 event Child tax credit's monthly check

As small tablets fade, iPhone 6 may come just in time

The rumored iPhone 6 is late to the big-screen party, but that likely won't stop lots of people from buying it.

iPad Mini: An Apple 'phablet' may make some consumers think twice about buying a Mini. Apple

Research is pointing to a growing preference for large smartphones over small tablets. That means the rumored iPhone 6 can't arrive too soon.

Market researcher NPD DisplaySearch said this week that for the first time global tablet shipments declined year to year in the first quarter of 2014. One of the culprits is smartphones with displays big enough to make consumers think twice about buying a tablet.

DisplaySearch expects that smartphones with display sizes of 5.5 inches and larger will negatively impact demand for tablets through 2018.

Problem is, Apple doesn't have a big smartphone. Which means it's late to the large-screen smartphone party, as analyst Mike Walkley from investment firm Canaccord Genuity said on Friday.

"The upcoming launch of 4.7 [inch] and 5.5 [inch] iPhones are the form factors Apple should have brought to market [last year]," Walkley said.

Apple's main rival Samsung has had large-screen phones for a few years now as have all the other major players like LG and Motorola.

But better late than never. Apple's tardiness isn't expected to impact the market acceptance of the rumored 4.7-inch and 5.5-inch phones.

Canaccord is boosting estimates for iPhone shipments in fiscal 2014 by several million and in 2015 by 10 million and consequently lowered its iPad estimates.

"Given our expectations for a very strong iPhone 6 upgrade cycle [that] could shift consumer spending away from iPads," Walkley said.

Of the two rumored models, the 5.5-inch device could give the iPad Mini the most trouble. The extra portability combined with the relatively large display for an iPhone (and possibly better battery life than iPhones to date) could lure enough consumers away from the Mini that sales suffer.

By comparison, Microsoft may already see the writing on the wall. It has either canceled or postponed the Surface Mini and has large phablet-class Nokia products like the Lumia 1520.

While Apple won't cancel the iPad Mini, its heyday is probably over.