Apple's former ad slogan was "Think different," but today's media event might have been tagged "Think small." Apple unveiled more compact versions of its iPhone and iPad Pro, plus new watchbands and updates to iOS and TVOS.

iPhone SE

The new 4-inch iPhone SE is a replacement for Apple's 4-inch iPhone 5S, which Apple released in 2013. Despite the success of its larger 4.7- and 5.5-inch iPhones, Apple said the smaller model remains popular, especially with first-time buyers -- 30 million 4-inch iPhones were sold in 2015.

On the outside, the SE looks similar to the iPhone 5S, but on the inside, it's much closer to the iPhone 6S. The SE sports the latest Apple A9 chip and M9 motion coprocessor found in the larger phones, comes with a 12-megapixel iSight camera, and can capture Live Photos and 4K video. It handles Apple Pay via TouchID and an NFC chip and supports the 802.11ac wireless standard for speedy connections. Available in silver, gold, space gray, and rose gold, the 16GB model will cost $399, and the 64GB model will go for $499. You can order today, and the phone starts shipping March 31.

iPhone SE

iPad Pro

The new 9.7-inch iPad Pro may be small, weighing less than one pound, but it is feature packed. Like the broad-beamed 12.9-inch iPad Pro Apple released last fall, the smaller Pro employs the fastest-ever 64-bit A9X chip and M9 coprocessor.

The display has a lot to recommend it: lower reflectivity, greater brightness and color saturation, and True Tone Display, which senses the color temperature of ambient light and adjusts to match. So you won't see the same tone at the beach as you do at the coffee shop, making for easier viewing and reading.

The smaller iPad Pro offers four speakers for improved sound and a back-facing 12-megapixel iSight camera (up from 8 megapixels in the larger iPad Pro), which can capture 4K video and Live Photos. The front-facing 5-megapixel FaceTime HD camera now incorporates Retina Flash. The True Tone flash feature makes skin tones lucid no matter how awful the lighting.

A Smart Connector pairs with a new Smart Keyboard with a smaller form factor. The new iPad works with the Apple Pencil and -- if you feel like going hands free -- Hey Siri. Prices start at $599 for the 32GB model and go up to $749 for 128GB and $899 for 256GB. You can order starting March 24 for shipment on March 31.

iPad Pro

iOS 9.3

iOS 9 is already running on 80 percent of active devices, and now 9.3 offers promising enhancements that should encourage more iPhone and iPad users to upgrade. Night Shift wants to make evening browsing easier on your eyes and better for your sleep. It determines when the sun has gone down (using your device's clock and geolocation) and then shifts screen colors to the warmer end of the spectrum. In the morning, the display returns to your regular settings.

The update also lets you lock Notes items behind Touch ID and password protection. New CarPlay capabilities for Apple Maps help you find gas, parking, restaurants, coffee, and other locations with a tap.

Native apps are also vastly improved. Health, which now receives data from 2,500 apps, has added app suggestions for new ways get data to your dashboard. The News app has added Top Stories to make it easier to stay on top of current news. Apple Music has added New and For You to help you discover new music.

Apple Watch

Saying a third of Apple Watch wearers regularly change bands, Apple CEO Tim Cook rolled out its spring lineup, including woven nylon bands in a variety of colors, new sports and leather bands, and a Milanese loop.

Apple dropped the price of the most affordable 38mm Sport Watch to $299, down from $349.

Apple TV

An update to TVOS out today lets you organize apps into folders. You can also dictate to Apple TV, and Siri can interact with the App Store. You can also access your iCloud Photo Library.

Personal privacy and health

Cook kicked off the event with a brief celebration of Apple's 40th anniversary on April 1 and then made an ardent defense of Apple's commitment to personal privacy. He said that Apple has more than 1 billion devices in use around the world, and with that breadth comes a duty to help customers guard their information. "We have a responsibility to help you protect your data," Cook said. "We owe it to our customers and to our country. We will not shrink from this responsibility."

Apple also highlighted how extensively its ResearchKit tools are being used in medical research, noting that the largest Parkinson's study in history is taking advantage of ResearchKit. A new medical tool, CareKit, will allow researchers to create apps that support patients during recovery or following medical events. Apple said it will be open source and available in April.

El Capitan

Outside of the event, Apple pushed out an update to El Capitan, OS X 10.11.4. The update lets users view Live Photos through the Messages app and password-protect Notes files.

Joshua Rotter also contributed to this article.

Clifford Colby follows the Mac and Android markets for He's been an editor at Peachpit Press and a handful of now-dead computer magazines, including MacWeek, MacUser, and Corporate Computing.