Philately

Postage Stamps? OK, so this is why it is in the "Free discussion" section. I used to manage my coin collection in an Excel spreadsheet. And then I found Numista. This is the best on-line tool that I have found, and I will do my part to help it grow.

Here is my question... Is there a similar tool for postage stamps?

The U.S. Postal Service has recently come out with the USPS StampApp. Have any of you tried it? Is it any good?
What is better? And what do you use for stamps from other countries?

Thank you for helping me find the best on-line tool for postage stamp collecting.

Perhaps stampworld.com