5 stars: I rate USPS as #1, FedEx as #2, Amazon as #3, and UPS as #4, for predictable timeliness and carefulness. USPS, FedEx and Amazon are always reliable. FedEx and Amazon provide the best tracking by app. Amazon sometimes shows truck location, fun to be curbside as the truck arrives. FedEx app is first class, others not even close.
5 stars: The FedEx app is easy to use and it is reliable to track packages. I like getting updates and delivery notifications so that my packages don't sit outside and I don't realize they are there. I use it all the time.
4 stars: The layout and arrangement of the links/buttons that provide the customers' information could be a bit more intuitive or obvious. A little bit easier to find what you're looking for would be nice.
3 stars: The tracking is a little off, especially when being shipped from the USA to Canada and I'm guessing vice-versa. The terms need to be better when the package is being delivered to the border or another carrier on the other side of the border. Not just package is out for delivery, when it's still in the originating country. Other than that, the tracking info is updated frequently and the app has all the necessary features.
3 stars: Could be better. It's functional, does what it's supposed to usually. Its drawback is that it's delay updates need to be more consistent. It'll say something is delayed & that's all, it's very picky when it tells you why or how. And even though I set it to send notification...