I guess I find it odd that there is no official app from the US Postal Service (USPS). I found an older one that does not work on new Android OS's. Or maybe they are too busy dealing with rain, sleep and snow?????????
I now have the USPS mobile app. I found a version on one of the APK sites and sideloaded it. I was able to see a package scheduled for today - more miraculously, I was able to manually type in the 500 digit tracking number without error! So we shall see how it works out.