Faster! Bigger! Thinner! Revolutionary! Lighter! Breakthrough! Beautiful!

Tech companies use words like these at their product announcements and in their marketing materials for good reason. Suddenly, you just have to upgrade, because not doing so leaves you stuck in the past.

You could try to sell your old gadgets, but you might not get as much as you expected. Or you could be worried about the security of your sensitive information. Even wiping your gadgets might not keep them as safe as you'd hope.

If you’re keeping your old gadgets, you might as well put them to good use. Here are three things you can do to put your old tech back to work.

1. Use your old phone as a surveillance camera

By law, all mobile phones in the United States must be able to make emergency calls to 911, even without a wireless plan. As long as you have your old phone’s charger, you can keep it around for emergencies.

But there’s another thing you can do with your old phone that will help keep you and your family safe. If it’s a smartphone, you can turn it into a surveillance system.

Maybe you want to watch a specific drawer, medicine cabinet, jewelry box, your work cubicle, the door to your room if you have roommates or what's happening in your hotel room while you're out. The only thing you need for these tasks is a smartphone (or a tablet) and a monitoring app.

All you have to do is set up your smartphone on a stand, such as this one I sell in my store, and point the camera in the direction you want to watch. When the app detects movement, it will alert you, take pictures of the intruder and even sound an alarm to scare him off.

At the moment, few monitoring apps work for both Android and Apple, so I'll tell you about one for each.

Salient Eye

Android users can grab the free Salient Eye app. When your phone's camera senses motion, it alerts you by email or text, starts capturing photos of the intruder and uploads them to a free cloud storage account. A few seconds later, it triggers an audible alarm that, hopefully, scares the intruder away. You need a password to shut off the alarm.

For the notification and uploading features, you’ll need to have your gadget connected to a cellular or Wi-Fi network. It can capture images and sound the alarm without a connection, but that doesn’t do much good if the intruder steals the phone.

In situations where you know someone is coming in, like a cleaning person, you can turn off the alarm so you can see what they're doing but not alert them. You can also turn off notifications if you just want to use the device as a motion-activated alarm.

The developer claims Salient Eye can work up to 10 hours on battery alone, so it will work even in places where you can't plug in to an outlet, like a drawer or jewelry box, or on a camping trip. There's also a paid remote-control app that lets you turn it on and off from a distance.

Manything

Apple users will want to download the free Manything app. Like Salient Eye, Manything uses your gadget's camera to detect motion and trigger an alert. Unlike Salient Eye, it can also capture video and stream it live to the gadget you have with you. It also stores up to 12 hours of video in a free cloud account.

Manything has other fancy features, like adjustable motion sensitivity, programmable motion zones so it can watch very specific areas, easy time-lapse and a built-in remote control. You can also set up multiple gadgets and view them in the app on your main phone.

If you're feeling really adventurous, Manything has IFTTT support for triggering updates to social media or even triggering Internet-connected home appliances like some LED light bulbs. Your only limit is your imagination.

Use it to record activity around a bird feeder or know when a child leaves her room at night. You can also just stick with using it for security. As I said, it’s free, but there are paid options that let you use it with more than one camera or get more than 12 hours of cloud recording storage.

2. Use your old tablet as a digital photo frame

Do you have an old tablet? Turn it into a digital picture frame to show off your vacations, kids, grandkids or anything else. You can also use an old computer if you don't mind it taking up space.

All you need to do is load up an app like Digital Photo Frame for Apple and Dayframe for Android. You can also use a website like Photosnack.

They all pull photos from your tablet or computer or your online accounts and run them as a slideshow. Dayframe also lets you stream your slideshow to a TV if you have a Chromecast streaming gadget.

To create a digital photo frame out of a computer, you can also use its built-in screensaver. To start, put the images you want to show in a folder. In Windows, the screensaver is under Control Panel>>Personalize. For Mac, it's Settings and Preferences>>Screensaver. Choose the folder of images you want to display and let the computer do the rest.

Want even more uses for an old tablet? I've got 9 more for you to try.

3. You can revive an old computer

You know the frustration of a computer that keeps getting slower and slower every year. There are ways to keep the speed up on an old computer, but eventually the hardware will become too outdated to run new software.

In the past, that's when you'd just go buy a new computer. But now it’s easier to give your old computer a second lease on life or turn it into a usable computer for a friend or relative.

All you need is one simple thing: the right operating system. And I don't mean you should just upgrade to Windows 10. It runs a lot better than past Windows versions on low-powered hardware, but it doesn't play nicely with your old hardware. To avoid this problem, you'll need to update to an operating system that isn't Windows.

Many people like using Linux, which is a free, secure operating system that comes in a lot of versions. But there is a simpler option. Over the last few years, you've probably heard about Chromebooks, sub-$250 laptops that run Google's Chrome OS, which is an operating system version of Google's Chrome browser.

Chrome OS works a lot like Windows. It has a start button, taskbar and apps, so you can pick it up quickly. Most of the time, it's as easy to use as a standard Web browser, and it can do many of the same things other operating systems can do, like video chat, play music, print documents and play games.

In the past, you'd need to shell out a few hundred dollars for a Chromebook or a Chrome OS-based desktop to get Chrome OS. But that isn't the case anymore.

A company called Neverware has an operating system called CloudReady, which is a version of Chrome OS that works on a wide range of laptops and desktops, including Apple hardware. The best part is that it's free for home use (there's also a paid educational version that's great for school environments).

Installing a new operating system is always a little tricky, but Neverware has extensive step-by-step directions on its site. It has also tested CloudReady on each of its "certified hardware models," so it knows what features do and don't work correctly.

You can check the list of certified hardware models to see if your laptop or desktop qualifies and how well CloudReady will work. Even if your model isn't on the list, you can install the OS anyway and see what happens. Many people have found it works just fine.

In general, CloudReady runs on laptops and desktops made after 2006, and on Netbooks made after 2008. It needs at least 1GB of RAM to run smoothly, but because it relies a lot on cloud storage and web apps, it needs only 8GB of storage space.

If you don't want to give up Windows entirely, you can dual-boot it and CloudReady on some computers. As always, be sure to back up your information in case something goes wrong during installation.

Of course, some people want to stick with Windows. If that's the case for you, then it's probably time to start looking for a new computer. The process can feel daunting, but it won't be if you know what to look for. Or you might decide you don't need a computer at all. These days, there are plenty of tablets that make excellent alternatives. Click here if you’d like more tips on what to look for.

Copyright 2016, WestStar Multimedia Entertainment. All rights reserved.

Kim Komando hosts the nation’s largest weekend radio talk show as she takes calls and dispenses advice on today’s digital lifestyle. Visit Komando.com for free podcasts, videos, product reviews, shows, tips and advice.