The Apple Watch has its own grid of apps that can be scrolled through. You can install quite a few on the included 6GB of available memory.
Twitter's app lets you browse recent tweets and trending hashtags. You can also favorite, retweet and reply to your tweets on the go. It's basic, but good.
Passbook puts Apple's wallet for QR codes and boarding passes on the Apple Watch, and it's really useful. You can pay for things by scanning QR codes at stores, or check into flights.
Evernote shows your notes on the go, and also allows you to create new ones by voice dictation, which is pretty useful.
Dark Sky is another type of weather app -- there's already Apple's own, which works fine, but Dark Sky shows immediate weather forecasts in your area.
MLB.com At Bat shows scores and stat updates for games in progress at a glance.
Apple's Maps app shows where you are, and can be zoomed in and out using the Digital Crown. You can also get turn-by-turn directions for walking or driving.
TripAdvisor shows nearby restaurants and places to go, including reviews. The app's not pretty, but it works.
CNN's app shows breaking headlines and brief summaries of multiple of stories at once.
The New York Times app also shows headlines and one-sentence summaries, but for far fewer stories and in a larger typeface.
The fun iPhone game, which tests memory recall, runs on the Apple Watch, but it's far more pared-down, less challenging and a bit of a letdown. But it's free if you already bought the great game on your phone.
With Uber you can call a car from your watch. It shows the estimated arrival time of the car and where your car is on a map.
A preinstalled weather app shows precipitation and temperature in a ring, like a watch face.
You can store photos on the Apple Watch like a little photo wallet, up to 500 photos at a time.
Apple's more exercise-targeted app lets you track runs, walks, cycling, elliptical, rower or stair-stepper workouts, by using heart rate and also your phone's GPS for outdoor activity. You can set goals for distance, calorie burn or time.
Yes, Trivia Crack lives on Apple Watch! It's a good fit with its simple layout, but you need to start a game on your iPhone first.
The onboard Music app works like a remote to access all the music on the iPhone, and also controls any third-party music apps you may have playing. You can store playlists on the Watch, too -- up to 2GB of music. You need to use Bluetooth headphones with Apple Watch if you're using it as an iPod.
One of few productivity apps on the Apple Watch, Invoice2Go lets you record your time on the fly for billable hours (or minutes).
You can send giant animated emoji via the watch instead of texts, if you wish. My wife had mixed feelings about it.
Sketching little doodles to send friends with the Apple Watch is weird, but that's Digital Touch in a nutshell. It's cute, but there's only so much you can sketch on a small screen with your finger.
Your favorite contacts are stored on an easy-access wheel: dial up who you want to reach and you can call, text, or send a Digital Touch sketch/tap/heartbeat if they've got an Apple Watch too.
Apple's daily fitness app runs on the Apple Watch and the iPhone. It tracks active exercise, motion and time spent standing. Three daily goals may sound daunting, but it's a clever way to inspire progress, and the colorful design is elegant.