Alistair Barr

USA TODAY

SAN FRANCISCO — Apple plans to launch two larger iPhones this year and will likely avoid using the plastic exterior design of last year's 5c model, which has not sold as well as expected, The Wall Street Journal reported Thursday. 

Apple is developing an iPhone with a display larger than 4.5 inches measured diagonally, and a second version with a screen bigger than 5 inches, the newspaper said. 

Both new models are expected to feature metal casings similar to what is used on the current iPhone 5s.  Apple is expected to scrap the plastic exterior used on the iPhone 5c, the Journal added, citing unidentified people familiar with the situation. 

The phones, expected in the second half of 2014, won't include a curved display, a feature recently introduced by rivals such as Samsung Electronics.  The smaller of the two models is being prepared for mass production, while the larger-screen version is still in preliminary development, the WSJ reported. 

Apple spokeswoman Teresa Brewer declined to comment. 

So far, Apple's largest phone has sported a 4-inch display.  However, Samsung and other rivals have made bigger phones, including so-called phablets, that have sold well, particularly in Asia, a region where Apple is searching for growth. 

"It's a product category that's been missing from, Apple so this is good to see," said Alex Gauna, an analyst at JMP Securities. " I would much rather have seen Apple first to market with larger-screen phones rather than playing catch-up.  That would have given me much more comfort." 

Apple, which reports quarterly results on Monday, has been dogged by concern about thinning profit margins and slowing growth as a wave of cheaper smartphones running Google's Android operating system gained market share in recent years. 

Apple tried to tackle this last year with the iPhone 5c — a slightly cheaper version of its main smartphone, but with a colorful plastic case rather than the usual, more expensive aluminum body. 

However, the 5c was still not cheap enough for developing markets, such as Asia, while most consumers in the U.S. snapped up the high-end iPhone 5s. 

"The notion that Apple may not use plastic casing for the new larger phones is not a surprise," Gauna said. " The 5c has been a disappointment to market watchers and Apple internally." 

The analyst expects the larger iPhones will likely have aluminum bodies and be positioned as a premium device, similar to Samsung's Galaxy Note 3, which has a 5.7 inch display. 

The larger phones will be particularly crucial as Apple tries to sell more mobile devices in Asia.  Bigger screens are popular in the region for several reasons, according to Gauna. 

A larger screen with a stylus is helpful for writing Asian characters, such as Kanji.  Bigger phones are also popular with less wealthy consumers who cannot afford to buy a smartphone and a tablet, the analyst said. 

Finally, there are more commuters who use public transport in Asia, and they prefer bigger screens for watching videos and playing games while traveling to and from work, Gauna explained.