Apple's upcoming iPhone comes at an unprecedented time for the technology giant, after disruption to its supply chain amid the global coronavirus pandemic.
The iPhone 12 - the rumoured name for the new phone - will succeed the iPhone 11 and iPhone 11 Pro as the flagship smartphone in Apple's line up.
The new device is expected to come with changes to Face ID, improved camera and screen technology and a much bigger battery. It is also expected to come with 5G - faster network technology that will make downloads quicker.
When the new model launches, it will come with Apple's latest iOS 14 software, while Apple is also expected to launch a new bundle of its subscription products for TV, music and games. Apple is rumoured to have ordered 75 million new phones in anticipation of orders for the latest generation of devices.
In addition to the new iPhone, Apple is gearing up to launch a slew of other devices including a new iPad, Apple Watch, HomePod and over-ear headphones, according to Bloomberg.
The company has faced a turbulent market on its road to a launch day amid delays due to the coronavirus pandemic.
Here is everything we know so far about the iPhone 12.
When will the iPhone 12 be released?
Apple normally launches its premium iPhone range in September, although its iPhone X had a later release date in November. It also released its cheaper iPhone SE in April.
This year, however, Apple has said its iPhones - still the company's biggest seller - will be delayed by several weeks, which eats into the number of days that shoppers have to buy them before the holidays and could lead to lower sales.
Analysts expect Apple to unveil a 5G iPhone and other updates at an event in October, with products going on sale later that month.
What is happening at today's launch event?
While the new iPhone won't be unveiled this month, the company will still announce a range of updates to some of its other key products later this evening.
The virtual 'Time Flies' event, which starts at 6pm BST today and can be watched from our live blog, will see Apple update its Watch and iPad Air.
The Apple Watch, likely to be called the Series 6, with features such as a faster processor and a blood oxygen meter. Apple is also readying its first update to the iPad Air since re-launching the line in March 2019. The new model will look similar to the iPad Pro by replacing the home button with an all-screen look. It will use a slower processor and lack some features such as the iPad Pro’s ProMotion screen.
The release of a new iPad and Apple Watches will correspond with the rollout of iOS 14, iPadOS 14 and watchOS 7 software updates this month. The company is also gearing up to announce Apple One services bundles.
Part of Apple's task Tuesday will be to make the case that products like the Apple Watch help keep customers in Apple's ecosystem over the longer term - even if they do not buy a flagship iPhone as a holiday gift.
"If sales happen to be softer than usual during the holiday quarter, that doesn't mean they're lost just because they're delayed," said Ben Bajarin, principal analyst for consumer market intelligence at Creative Strategies.
What will the new iPhone be called?
The new iPhone is expected to be broadly known as the iPhone 12, but there could be several different variants with different sizes and specs. Analysts expect four new iPhones.
These will be the iPhone 12, which will have a 5.4-inch screen and a possible larger iPhone 12 Max with a 6.1-inch screen. Rumours have it that these phones will come with dual rear cameras and the capability to connect to 5G networks.
There will also be a more powerful iPhone 12 Pro with a 6.1-inch screen and a larger iPhone 12 Pro Max coming in with a 6.7-inch display. These phones are said to come with triple rear cameras and 5G connectivity.
The new iPhones are expected to come with then new option of a dark blue colour.
New features to expect on the iPhone 12
At least some of the new iPhone devices coming in September are expected to come with the ability to connect to 5G networks. These phones will come with 5G modem chips, most likely from Qualcomm. Phones with 5G connectivity offer faster download speeds giving the ability to download or stream high definition films and games in seconds.
New sizes and screen technology
The four new iPhones are expected to come in several new sizes, split into two high-end devices and two cheaper devices. The smallest iPhone 12 model is, according to reports, going to have an approximately 5.4-inch screen, while two other models will have 6.1-inch screens. The largest phone will have a 6.7-inch screen. The Pro versions are also expected to come with 120Hz screen refresh rates, meaning the screens are more responsive for gaming.
Apple's phones currently come with Face ID technology on their front-facing cameras. This uses 3D depth sensing camera technology to read a user's face. Now, Apple is planning to improve its rear cameras on at least some of its phones with similar technology to add better augmented reality capabilities. This will see it come with a Lidar laser scanner that can create more accurate augmented reality objects.
According to Apple tipster Max Weinbach, the new iPhone will also come with improved camera technology that offers 3 times zoom, rather than the 2 times zoom it currently has.
The largest new iPhone is expected to come with an even larger battery than on previous models, according to Weinbach. It is expected to have up to a 4,400mAh battery, according to Weinbach.
No headphones or charger?
Yes, this year the new iPhones are also said to be the first sold without a bundled power adapter or a set of wired headphones. Analysts at TF Securities and Barclays have both predicted Apple will keep the charging cable that comes in the box, but ditch the wall plug.
This is likely to annoy anyone new switching to an iPhone if they lack the necessary adapters and have to splash extra money on new wires from Apple. However, as James Titcomb writes, it is probably not a bad thing to cut out all that unnecessary e-waste.
Apple One bundles
Apple is planning to launch a new subscription package that will give consumers a way to pay for multiple Apple services for a small discount.
The new offering is expected to be called Apple One, according to Bloomberg. It will see Apple's TV+, Music, Arcade and iCloud storage thrown together into bundles that will come with a discount of a few pounds. The subscription bundles will keep consumers loyal.
They will also take advantage of 5G connectivity speeds for streaming movies and mobile games.
A new iPad, Apple Watch, HomePod and headphones
Apple is planning a host of new devices to come out around the same time as its new iPhone. These include a revamped iPad with squarer edges, similar to its current iPad Pro, according to Bloomberg. It will also refresh the Apple Watch, which is likely to include a cheaper version to compete with rivals such as FitBit. Apple is also likely to renew its HomePod smartspeaker with a cheaper, smaller device than the original it released in 2018.
Perhaps most anticipated will be Apple's first set of over-ear headphones outside of its Beats brand. These headphones could win over fans after the success of its AirPod in-ear headphones.
How much will the new iPhone 12 cost?
The new devices are expected to come with several different levels of storage - between 128GB, 256GB and 512GB - which will affect their prices.
According to Jon Prosser of FrontPageTech, the regular iPhone 12 will start at $649 (£526), the iPhone 12 Max at $749, iPhone 12 Pro at $999 and iPhone 12 Pro Max at $1,099. There are currently no UK price estimates.