The first-generation iPad was unveiled by the then-Apple CEO Steve Jobs on Jan. 27, 2010, with the Wi-Fi variant released in the US on April 3, followed up by the Wi-Fi and cellular variant April 30 (the iPad was subsequently released in Australia, Canada, France, Japan, Italy, Germany, Spain, Switzerland and the UK on May 28).
During its unveiling, it's fair to say that the media and consumer reaction to the iPad was mixed. Some became overly focused on the hilarity of the name (names such as iSlate or iTablet had been swirling around the rumor mill ahead of the unveiling), the lack of a software ecosystem, and the lack of features such as printing file-sharing, while others saw it as a logical follow-on to the iPhone and giving Apple an advantage over the Android platform (the first Android tablet -- the Samsung Galaxy Tab 7.0 -- was introduced on Sept. 2, 2010 and released a month later).
The first iPad featured a 9.7-inch 1024 × 768-pixel (132 pixel-per-inch) IPS LCD touchscreen display. This display was powered by Apple's A4 System-on-a-Chip (SoC), which consisted of a 1GHz ARM Cortex-A8 processor, and a PowerVR SGX535 GPU, and this was backed up by 256MB of DDR RAM. Storage options ranged from 16GB to 64GB, and prices starting at $499.
Fueling this hardware was a 6,613mAh lithium-polymer battery that offered 10 hours of battery life, setting a standard that continues to this day.
Apple sold 300,000 iPads on day one, and in a month, this had increased to a million, hitting this milestone in half the time it took the iPhone to do it.
The first iPad initially ran iOS 3.2, and was upgraded several times over its life, culminating with iOS 5.1.1 -- following its discontinuation on March 2 2011 and support ending on Sept. 18, 2012.
On March 11, 2011, less than a year after the original iPad was released, Apple released the iPad 2. As well as upgrading the SoC to the Apple A5 chip that consisted of a 1 GHz dual-core 32-bit Cortex-A9 CPU and dual-core PowerVR SGX543MP2 GPU, and upping the RAM to 512MB, the iPad 2 also introduced to the iPad front- and rear-facing cameras.
All this was built into a smaller, lighter chassis (15 percent lighter and 33 percent thinner than the original iPad).
Apple sold more than a million iPad 2 devices over the first weekend, and sold some 35 million during 2011.
This was followed up a year later by the third-generation iPad, which Apple called "The new iPad," but which was more commonly referred to as the iPad 3. This saw the SoC upgraded to the Apple A5X, which featured a 1 GHz dual-core 32-bit Cortex-A9 CPU and a quad-core PowerVR SGX543MP4 GPU. The RAM was also bumped up to 1GB and connectivity upgraded to support LTE (4G).
But the biggest upgrade that the iPad 3 brought to the line was a 2048 × 1536 pixel IPS LCD Retina display with a pixel density of 264ppi, offering four times the pixels of the iPad 2.
But despite selling three million units over the first three days of availability, and going on to capture over 69 percent of the global tablet market, the iPad 3 was discontinued after only seven months.
October 2012 saw Apple diversify the iPad line by introducing the iPad 4, powered by the upgraded Apple A6X chip (which features a 1.4GHz dual-core chip with benchmarked as being twice as fast as its predecessor), expanding storage capacities to 16 GB, 32 GB, 64 GB, and 128 GB, and doing away with the 30-pin connector and replacing it with the now familiar Lightning port.
At the same time, Apple unveiled the first iPad mini, which was essentially an iPad 3 with a 7.9-inch 1024 x 768 pixel (163 pixel-per-inch) non-Retina display, half the RAM (512MB), and a Lightning port.
The smaller screen and lower price (starting at $329), positioned the iPad mini against devices such as Amazon's Kindle Fire HD or the Google Nexus 7.
November 2013 saw Apple first release the iPad Air (Nov. 1), followed by the iPad mini 2 (Nov. 12).
Along with its upgraded hardware silicon (introducing the 64-bit Apple A7 SoC) and improved cameras, the iPad Air saw a design change, which made it thinner and lighter, and cutting down the size of the screen bezel.
The iPad mini 2 was essentially a scaled-down iPad Air, and was the first iPad mini to feature a Retina display (a 2048 × 1536 pixel, 326ppi panel).
It was also the first iPad to feature stereo speakers.
Despite being first released in 2013, and since being discontinued, both of these iPads are still supported by Apple and both can run the latest iOS 12 release.
October 2014 saw Apple do the thing that people were by now expecting of it and release upgrades for both the Air and mini iPads.
The iPad Air 2 not only featured the Apple A8X chip, but also sported the Touch ID fingerprint-reader Home button already shipping on the iPhone. The iPad mini 3 was essentially an iPad mini 2, which featured a Touch ID Home button and the option of a gold finish.
On both fronts this represented evolution, not revolution.
Now we come November 2015 and we see Apple take the iPad and super-size it into the iPad Pro. This device sported a 12.9-inch 2732 × 2048 pixel True Tone IPS LCD display, a dual-core A9X chip, and storage capacities ranging from 32GB to 256GB.
This was also the first iPad to ship with 4GB of RAM. It also featured a smart connector specifically designed for keyboards and four stereo speakers located at the top and bottom of the device.
The iPad Pro was Apple's response to the increasing popularity of larger tablets, both from the Android and, increasingly, Windows camps. With the "Pro" moniker, not only was this 12.9-inch iPad being aimed at high-end business users, but also creative types who would want to edit photos or video on the move, or create digital artwork while at or away from their desks.
Prices ranged from $799.99 to $1,229.99, depending on storage capacity and connectivity options.
The iPad mini 4, which was unveiled alongside the iPad Pro but released in September 2015, represented Apple's first major design tweak of the iPad mini line since its release. The iPad mini 4 was taller and wider, yet thinner and lighter than its predecessors, and the internals were upgraded to bring it closer in line to the iPad Air 2.
On March 21, 2016, Apple released a 9.7-inch variant of the iPad Pro, building on the foundations of the iPad Air 2 by adding a faster processor and GPU, and improved camera complete with True Tone Flash and Retina Flash.
Compared to the 12.9-inch iPad Pro, the 9.7-inch variant is essentially the same, except for the smaller screen, a slightly slower processor, and half the RAM (2GB instead of 4GB).
Prices ranged from $599 to $1,129 depending on the variant and storage options.
Fast forward to 2017 and Apple finally releases the fifth-generation iPad. This device represents a refresh that places this device between the iPad Air 2 and the iPad Pro. But it's clear from the price -- $329 -- that this device is aimed at those more concerned about price than power and performance.
Apple unveiled the second-generation iPad Pros at WWDC 2017 on June 5, 2017. And it built on the existing iPad Pro lineup.
Two iPads Pro tablets were unveiled at the event -- 10.5-inch and 12.9-inch versions, both powered by an A10X hexacore CPU and 12-core GPU, both featuring 4GB of RAM, and both featuring a 12-megapixel rear-facing camera complete with quad-LED True Tone flash, and a 7-megapixel front-facing FaceTime camera.
On the charging front, these were the first iPads to support USB-C fast-charging and data transfer rates (with the appropriate USB-C-to-Lightning cable).
The second-generation iPad Pros were offered with 64GB, 256GB, and 512GB storage capacities.
On March 27 of 2018, Apple released the sixth-generation iPad. All-in-all, this was rather a minor upgrade, with the SoC bumped up to the Apple A10 Fusion chip (which first appeared in the iPhone 7), and adding support for the Apple Pencil.
The focus of the launch was education, and Apple's renewed efforts to get the iPad into classrooms. It even offered schools a discounted price of $299 (as opposed to the regular price of $329).
Released on October 30 of 2018, the third-generation 11-inch and 12.9-inch iPad Pro was a major upgrade. Not only did the device get a new processor -- the A12 Bionic -- but it also featured Face ID, an edge-to-edge Liquid Retina displays, upgraded 12MP and 7MP cameras, and, most importantly, a USB-C connector.
Gone though is the headphone jack.
Also, for those who want to carry a lot of data, the third-generation iPad Pros offered up to 1TB of storage.
It took a long time, but on March 18, 2019, Apple unveiled an updated iPad Air.
The processor was bumped up to the Apple A12 Bionic chip, and the display upgraded 10.5-inch Retina Display panel that offered support for first-generation Apple Pencil.
There are two storage options available -- 64 or 256 GB -- and while the rear camera continued to be an 8-megapixel unit capable of recording 1080p, the front-camera was upgraded to 7-megapixel, as found in the iPhone 7 and iPhone XS.
Apple pushed out the fifth-generation iPad mini on March 18, 2019 without the fanfare of a press event.
The processor was bumped up to the Apple A12 Bionic chip, and the display upgraded 7.9-inch Retina Display panel that offered support for first-generation Apple Pencil.
There are two storage options available -- 64 or 256 GB -- and while the rear camera continued to be an 8-megapixel unit capable of recording 1080p, the front-camera was upgraded to 7-megapixel, as found in the iPhone 7 and iPhone XS (same as the third-generation iPad Air).
On September 25, 2019, Apple made a play for the education market with the release of the seventh-generation iPad. While this iPad got a display upgrade to a 10.2-inch display with support for first-generation Apple Pencil. However, the processor wasn't, using the existing Apple A10 Fusion chip (which first appeared in the iPhone 7).
On the plus side, the RAM was bumped from 2GB to 3GB, which for a budget device with a starting price of $329, is not too bad.
Here's a chart showing quarterly iPad sales to the end of 2018 -- the point at which Apple stopped releasing sales figures for hardware. As is clearly shown, the iPad's heyday is long behind it, but with quarterly sales hovering around the 10 million mark, it's clear that the iPad is far from being a dead product.