The iPhone 6 and the Galaxy S5 are probably the two most-anticipated new handsets expected this year. We’re constantly hearing supposed leaks and speculations about what they will have or how they will look. Just filtering out the nonsense from all of the chatter is nearly impossible, but here are some of the details which have at least a decent chance of appearing in these handsets this year.

iPhone 6

iPhone 6 could feature sapphire glass

One of the most interesting reports we heard pertaining to the iPhone 6 on Friday was about sapphire glass. ABC News interviewed Apple Inc. (NASDAQ:AAPL) CEO Tim Cook about the 30th anniversary of the Mac computer, and one of the things they asked about was the use of sapphire glass, possibly for the iPhone 6. Apple did make a significant investment into the facilities run by sapphire glass maker GT Advanced Technologies recently.

All Cook would say was that the sapphire glass wasn’t necessarily for the next-generation iPhone but that he couldn’t discuss it right now. They then asked him if the sapphire glass was for the rumored iWatch, and in response, he joked (let’s hope anyway) that they were actually making an iRing.

Apple suppliers said to make sapphire prototypes

What makes Cook’s comments especially interesting is a report on Chinese website Apple Daily, which was spotted by Apple Insider. The report indicates that Apple supplier Foxconn recently assembled 100 or more prototype iPhones with displays that are covered in sapphire. The report on the Chinese website also notes that two of Apple’s current sapphire suppliers have invested in more equipment and tooling recently and that Apple already uses 10% of the world’s manufactured sapphire.

In addition, it indicates that the use of the sapphire glass made the manufacturing process much more complex. This could be why Cook didn’t say that the iPhone 6 definitely would or wouldn’t have sapphire glass because this aspect of the design might still be up in the air right now, depending on whether they can pull it off in time to include the glass in the iPhone 6 this year.

Will Galaxy S5 have a metal casing?

While we’re on the topic of materials, we still have the question of whether the Galaxy S5 will have a metal casing. Many Samsung fans are hoping it will, although we still have conflicting reports on this topic. This is a debate which will probably happen every year until Samsung finally launches a handset with a metal casing. The Korean electronics giant was said to have scrapped the idea of a metal casing for the Galaxy S5 because it was too expensive, but then we started hearing that there might be not one, but two new premium handsets from Samsung this year, one of which would have a metal backing.

Galaxy S5

There are still some murmurings within the industry which suggest that we’ll see an even more premium Galaxy model—perhaps called the Galaxy F—along with the Galaxy S5 this year. These reports suggest that this might be where Samsung will use metal casings, which might make sense because the company could charge more for them in order to make up for the cost of using metal.

Guessing screen sizes

Of course we’ve also been hearing numerous reports that Apple Inc. (NASDAQ:AAPL) is also planning two new premium handsets this year. Reports from numerous sources have suggested that the iPhone 6 will come in two different screen sizes: one that’s a little under 5 inches in size and a second with a screen size approaching 6 inches.

There are even rumors that the size of the Galaxy S5’s screen will get a bump up this year. Gotta Be Mobile points to a supposed leak from Kipris which suggests that the handset will have a 5.25-inch screen with a higher QHD resolution. Perhaps the biggest problem with these big phones is using them with one hand—an issue Apple has referenced when asked previously why it hasn’t launched a larger iPhone.

This particular alleged leak also shows a new interface which features touch areas in the corners of the screens which make it easier for users to access shortcuts to various settings and apps. The source does emphasize though that this UI may not end up being the final one selected by Samsung for use in the Galaxy S5. This is interesting because of another supposed leak from Twitter tipster @evleaks which also suggests that the Galaxy S5 will sport a much different UI—one that in fact looks more like Windows Phone than Android.

Other features we could see

In addition to the suggestion of a bigger Galaxy S5 screen and a new one-hand-friendly UI, this same alleged leak suggests Samsung could be including a new music app. This feature would make sense as the company needs to stay in step with Apple iTunes Radio, which launched in 2013, and Pandora Media Inc (NYSE:P), which remains a popular streaming music app. The Galaxy S5 could also join the iPhone in featuring a 64-bit chip, which included in the iPhone 5S last year.

In addition, biometrics is getting to be a hot topic. Analysts speculate that Apple will improve the functionality of the Touch ID sensor for use in mobile payments. Samsung executives have also confirmed that they’re working on an iris scanner, but they weren’t sure yet if it would be included in the Galaxy S5 this year. Apple and Samsung are now locked in a race to see which of them can include an iris scanner first.

Speculating on release dates for iPhone 6, Galaxy S5

And finally, we have rumors about the launch dates for the iPhone 6 and the Galaxy S5. It’s pretty much a guarantee that the Galaxy S5 will come out before the iPhone 6. Many have speculated that it will be previewed or even launched in March and launched in April, while others have suggested that it will be previewed at the Mobile World Congress in February and then launched in March. Still others say that Samsung is now unsure about when and where to announce the Galaxy S5. That last one comes via a tweet from Eldar Murtazin of Mobile Review (spotted by NDTV Gadgets).

But speculations about the iPhone 6 release date vary much more widely than those for the Galaxy S5 do. Some say the iPhone 6 will be out as early as June, while others are betting on a fall release date, which would follow Apple typical launch pattern for past iPhones.