That is, unless you want to get a bad rating.

Last week, Uber agreed to let drivers start requesting tips from their customers.

For people who don't use Uber, this might sound a little confusing. "Isn't Uber like a cab? Shouldn't you already be tipping your driver?" Well, you kind of already were . Uber came up with a way of doing things entirely through the app, so that carrying cash with you was unnecessary. Those days are officially over. Now Uber drivers can posts signs in their vehicles letting you know that tipping is recommended and not included in your fare. And since there's no way to tip using you card on the app, that means you'll be needing cash.

You might be thinking, "what happens if I don't tip? What are they gonna do?" Well, the beauty of Uber is that you can rate your Uber driver, but your Uber driver can also rate YOU. That means that your driver can take your five-star rating down to a two, potentially making it more difficult for you to get picked up, since other drivers can see your individual rating. I'm not saying that all Uber drivers will react this way, but I don't think it's a crazy idea.

In recent months, I've come to know quite a few Uber drivers who has expressed to me how little they actually make, after paying for gas and car maintenance. When I have cash with me, I always give them a little extra at the end of the ride. The thing is, is I never carry cash. That's why I'm hoping that Uber will update the app to include a option to tip on your card, like Lyft does. I think that will make things a little easier for everyone.

What do you think of this change to Uber? Let us know in the comments.