The iPhone 15 Pro could be a major change to Apple's premium models. Instead, the change will be made only to the Pro model, meaning it will be a much tougher iPhone than ever before.

That's because Apple may choose titanium alloy as the frame metal for the iPhone 15 Pro and iPhone 15 Pro Max. The move would reduce weight and make the new phones more durable than previous models; in addition to changing the material used for the Pro models, Apple is expected to change from the straight edges of recent iPhones to more rounded edges.

However, it is the titanium rumor that has caught our eye, as it is a change that seems to have an immediate impact on your iPhone experience while potentially widening the gap between the iPhone 15 vs. Here's what we know about the rumors surrounding Apple's choice of material for the iPhone 15 and how the switch to a titanium frame could benefit you.

The material used for the frame of the current iPhone depends on which model we are talking about. The standard iPhone uses aluminum, as does the iPhone 14 Plus (and earlier iPhone mini models). The more expensive Pro models use a stainless steel alloy for the frame.

Apple's alleged switch from stainless steel to titanium predates the iPhone 15 buzz; a year ago, some sources were leaning that the iPhone 14 Pro would get a titanium frame.

Will that be a new story this year, some leakers certainly think so, as rumors of a titanium-based model for the iPhone 15 have been floating around since shortly after the iPhone 14's release. The rumor at the time was that the material would be part of the iPhone 15 Ultra device, which, depending on who you ask, would either replace the iPhone 15 Pro Max in Apple's lineup or appear as another high-end phone.

The iPhone 15 Ultra rumor has since subsided, but talk of a titanium-based iPhone continues. And more than just anonymous leakers on Twitter are touting the possibility of a change. Jeff Pu, an analyst at Haitong International Securities in Hong Kong, included a titanium frame in a list of expected iPhone 15 Pro features he shared in a research note; Bloomberg's Mark Gurman also listed titanium as an iPhone 15 Pro feature as titanium.

The best indication of the new iPhone 15 Pro's material comes from a Patently Apple post citing two supply chain reports that seem to confirm the switch to titanium for the new model.

As noted above, titanium's appeal lies in its durability. Titanium is twice as strong as aluminum and about 30% stronger than steel. Stainless steel is prone to fatigue and shattering.

This could make the iPhone more durable. While the current iPhone is considered quite resilient, drop tests of the iPhone 14 showed some damage to the Pro after just one drop. Perhaps the addition of titanium would reduce the devastating damage.

Just as important as durability is weight, and titanium was found to be much lighter than stainless steel - a little over 40% lighter. The iPhone is not the bulkiest phone around - the iPhone 14 Pro Max is the heaviest Apple phone at 8.47 ounces - but every little bit helps.

That said, if Apple decides to add other components, the iPhone 15 Pro model may not be significantly lighter than its predecessor. For example, the iPhone 15 Pro Max is said to have a periscope-style telephoto lens, which may require more components than the current camera setup. Therefore, consider the lighter titanium a way to offset the extra weight that the iPhone 15 Pro model will carry.

Titanium has one potential disadvantage. By switching to more expensive materials, Apple may be forced to increase the cost of the Pro model; it is probably no coincidence that the iPhone 15 Pro pricing rumors suggest a $100 price increase for the Pro and Pro Max.

Apple's iPhone plans will not be clear until the September Apple event, when Apple is expected to unveil the new devices. However, the fact that several sources have included a titanium frame in their iPhone 15 Pro predictions - including Apple watchers with a proven track record when it comes to unannounced products - suggests the presence of this feature.

One potential red flag is the fact that the titanium frame was first touted as an iPhone Ultra feature. iPhone 15 Ultra may not materialize this year, but many people believe that an Ultra model is being planned for. If so, Apple may reserve the titanium frame exclusively for the iPhone Ultra, and this would be the second consecutive iPhone announcement where the Pro model was said to have titanium, but did not include the feature.

For now, however, the conventional thinking is that a titanium-based iPhone 15 Pro could well be on the horizon. And that would be a welcome change for those looking for a lighter, sturdier iPhone.