This week, Portland launched their new parking app that lets you pay for metered parking using your smartphone. It's very convenient but there are a couple of things you should you know before you choose to use it.

The best feature of the app is not having to dig for change or swipe a card and being able to add more time to the meter without having to physically go back out to it.

I used it for the first time today and found that the company that created and developed the app, Passport Parking, charges a 25 cent convenience fee.

Convenience fees aren't anything new. If you've ever ordered tickets online for a concert or a movie, you are charged a convenience fee. Something to keep in mind when using the app. To save the 25 cents, you can still pay at a meter.

The other thing to note when paying for parking with your phone is that unlike paying at a meter kiosk and putting a ticket on your dashboard, you can only park in the zone you have paid for. When you have a payment ticket on your dash, you can park anywhere in the city and even move from space to space as long as your time has not expired. That's not the case when paying from your phone.

Nevertheless, this is a very convenient was to pay for your parking if you don't mind the fee or being restricted to a specific zone. If you want to grab the app, here are the links.