The new iPhone 15 models are available for pre-order Friday, days after Apple's "Wonderlust" event previewing the offerings.

The Silicon Valley behemoth made both aesthetic and technological changes to their flagship product line, including new materials, upgrades to the camera and computing systems as well as a new colors.

The company's valuation crossed the $3 trillion mark in June. Apple's stock (AAPL) fell from a Tuesday opening of $179.49 per share to trading at $175.74 at the closing bell on Thursday.

Here's what to know about pre-orders for the new iPhone 15.

O'Donnell:The new iPhone 15 is a solid upgrade for people with old phones. Here's why

When will the iPhone 15 be available?

All four devices in the new iPhone lineup − iPhone 15, 15 Plus, 15 Pro and 15 Pro Max − will be available for preorder on Friday and available online and in stores on Sept. 22.

How much will the iPhone 15 cost?

The base model iPhone 15 will start at $799, while the 15 Plus will start at $899.

The iPhone 15 Pro starts at $999, while the iPhone Pro Max starts at $1,199.

What colors does the iPhone 15 come in?

The base models will debut in five colors – pink, black, white, blue and yellow.

The iPhones will have aluminum sides and a glass back like the iPhone 14 and 14 Plus. 

The iPhone Pro models will come in dark gray, black, dark blue and light grey and have titanium sides.

What's new in the iPhone 15?

The standard iPhone 15 models will have Dynamic Island, a redesigned notch at the top of the screen that takes up less visual space. The feature was first added to the iPhone 14 Pro models last year as a tool to track ongoing activity, like directions or the music you're listening to. 

Apple also added roadside assistance on the same system used for the SOS feature.

Drivers lost in an area without cell service will be able to trigger the feature via text, which will allow them to share their location via satellite.

The feature will launch with AAA as the roadside assistance provider and those who purchase an iPhone 15 will have access to the feature for two years.

The toggle for the mute function is gone on the iPhone 15 Pro models, replaced with a programmable action button.

All of the new iPhones will switch from Lightning to USB-C charging to comply with European Union common charger laws.

What camera systems will the iPhone 15 use?

The standard iPhone 15 models will have an improved camera system that will allow for greater optical zoom and a wide depth of field, switching from a 12-megapixel main camera sensor to a 48-megapixel version. 

The new camera has the same resolution as the camera on the iPhone 14 Pro.

The iPhone 15 Pro models will still have three cameras and a 48-megapixel main camera sensor. It will have new telephoto and ultrawide lenses with more megapixels than the iPhone 14 Pro. 

The iPhone 15 Pro Max will have an updated telephoto system with enhanced hardware zoom capabilities, which will double the iPhone’s ability to zoom into images with the physical lens from 3X to 5X at 120mm focal length.

What chips will the iPhone 15 use?

The iPhone 15 base models will use the A16 chip used in the iPhone 14 Pro models.

The iPhone 15 Pro models will have the faster A17 chip that the company claims will improve the mobile gaming experience.

Both phones will also have a “U2” ultrawide-band semiconductor, the first since the U1 launched in the iPhone 11 Pro. The new semiconductor improves the location feature, which allows the phone to be tracked more accurately in the Find My app.

Saltzmann:Is the new iPhone 15 worth it? 3 reasons to consider buying one.