If your vehicle is older, you might want to check this out. Harry Howitt/Shutterstock Car Play has become a must-have for many drivers. It's no surprise, since it makes life so much easier when it comes to accessing your i Phone apps in the car.

Navigation, music, messages — all right there on the dashboard. And while there are more than 800 Car Play-compatible vehicles, you might have one that isn't on the list. But no, you don't need to trade in your car.

Some portable screens can give you Car Play for much less. They aren't quite as good as built-in systems, but they get the job done. Despite all the convenience Car Play offers, some automakers have been getting rid of it.

GM, for example, has decided to phase out Car Play and Android Auto from its EVs. Yes, many people love Car Play. But they want you to use their own systems.

It's an understandable business move, considering that some even charge you to unlock extra features in their cars. Getting a portable Car Play screen ends up being a good way to get around this. What to look for when buying a portable Car Play screen Evgenia Parajanian/Getty Images Unlike buying a new car, getting one of these portable Car Play screens won't cost you much.

You can find many of them for under $50. Even if you pay $150 for one of these, it's still much cheaper than a new car. Some have larger displays and will cost more, and some really cheap ones might be best to avoid — those usually have really bad touchscreens.

Start by choosing the right size. Most of these range from 6 to 11 inches. Some users find large screens too distracting, so it might be worth going with a smaller one.

Smaller screens are easier to fit in your car, too. But size isn't the only thing that matters here. There are other specs you should consider, like screen resolution.

Some portable screens have very low resolution. It's not as if any of these screens were designed for watching 4K video — they weren't. But going with a low-resolution screen will make everything look terrible, from text to icons.

Look for screens with a resolution of at least 1280x720 pixels. The audio output is also a big plus. Most of these screens have awful speakers, so be sure to choose one that supports AUX, Bluetooth or FM for playing audio.

Also, make sure you're getting wireless Car Play instead of wired Car Play. Not every portable screen lets you use Car Play without a cable. Extra features they can offer you Bowonpat Sakaew/Shutterstock Even though these portable screens are designed for Car Play, some of them offer interesting extra features.

Many models include integrated dash cameras with micro SD loop recording. Others might come with a rear camera, which is nice for adding parking assistance to your old car. Also, keep an eye on how the display attaches to your dash.

Some of them have very unstable mounts, and you don't want your screen flying off as you turn a corner. And keep an eye out for screens that come with Android built in. That doesn't matter for running Car Play, but it lets you install apps that can run without your i Phone.

As you can see, buying one of these portable screens is an easy way to get around the lack of Car Play. They work and are cheaper than a retrofit to your car's built-in system. Sure, they won't look like a factory system, but that's fine.

For the price, you're still getting a great deal.