LOS ANGELES -- Apple has ways of encouraging you to buy more of its products: It offers bonus features on devices like the iPhone and iPad that work only when paired with other Apple gadgets.
Amazon does it, too.
It's understandable. The devices need to communicate with each other at a deep level, and that's more easily done when a company controls the software on both ends. And these features are more like extras and don't affect the products' basic functionality.
Take streaming TV devices, for example: These gadgets cost about $100 and let you watch Netflix, Hulu and other online services on a big-screen TV. Though you don't need any other device for basic streaming, some advanced features in Amazon's Fire TV require a Kindle Fire tablet or a Fire phone, while some Apple TV features work only with iPhones, iPads and Mac computers.
As a result, you're wise to consider the devices you already own when you buy a new gadget, as these devices become more powerful when combined. Here's a closer look at how the Apple TV and the Fire TV work with other gadgets from Apple and Amazon.
Amazon fire TV
With a Fire phone or tablet, you can start a movie or TV show on one device and continue on another, at least when you're using the company's own streaming service, Amazon Instant Video. When watching on the TV, you can have the phone or tablet display trivia, cast information and character summaries -- culled from IMDb and other sources. Information on the mobile device changes from scene to scene.
Consider these scenarios:
• You're near the end of a movie on the Fire TV at home, but need to head out. Just pull down the Fire phone's notification center and switch the movie to the phone. You won't miss a scene. It works the other way if you start on the phone on the way home.
• An actor seems familiar, but you can't remember his name or what else he's been in. With video playing on the Fire TV, check the phone or tablet to see headshots of actors in a given scene. Tap a headshot for more information. The feature also works with songs playing during certain scenes -- and you can buy the song through Amazon, of course.
• You can also use the phone or tablet to pause, rewind, forward or go directly to a specific scene on the TV. Or you can check Facebook and email on the device once you've had your fill of cast information.
What about streaming services beyond Amazon's? By turning on a screen-mirroring function, anything appearing on the phone or tablet will appear on the TV. You have to dig through the settings on the phone or tablet to turn it on, though. Beyond video, I had a lot of fun pointing the phone's camera at my cousins' kids so they could see themselves on the TV live.
Unfortunately, audio and lips had a tendency to be out of sync when I mirrored using my home Wi-Fi network. It's better to work with an app that directly supports dual-screen use. Only Amazon Instant Video does so for now, though Amazon says it's working with selected partners to expand that.
You can start video on an iPhone or an iPad and continue on the TV using a feature called Airplay. You're not limited to Apple's own iTunes service, so this is a way to get Amazon Instant Video on the big screen.
However, services have the option to disable this capability. Showtime and ABC Family, for instance, have done this. Their apps lack the Airplay button and aren't available on the Apple TV.
Apple doesn't offer supplementary information on cast and characters, as Amazon does. And while you can start something on a phone or tablet, switch to the TV and switch back, this doesn't work if you start the video on the TV. Amazon's devices work both ways.
Apple does offer screen mirroring, and it's easier to get to than Amazon's version. Just swipe up from the bottom for the Control Center. It's not true screen mirroring, as video disappears from the mobile device when it shows up on the TV. This actually improves video quality because you're not wasting Internet bandwidth duplicating the stream on a device you're not watching.
You can also do screen mirroring from a Mac or use the Apple TV as a second monitor to extend your Mac's desktop space. But it doesn't always work well if your Wi-Fi network isn't pristine.
Unfortunately, mirroring is sometimes blocked for copyright reasons. I'm not able to fling DVDs from the Mac to the Apple TV, for instance. In trying to fling Showtime and ABC Family from the phone or tablet, I can get only audio on the TV. I haven't run into that with any of the video apps I've tried on the Fire.
Beyond streaming TV, Apple devices will soon work together even more extensively. The upcoming Yosemite operating system for the Mac and iOS 8 for iPhones and iPads will have a set of features called Continuity. You can start an email on one device and finish on another. Or you can answer phone calls on the Mac. Stay tuned.