I would like you to please try to press the > icon in the top right corner of the widget. After I tested it on an iPad IOS 14.7.1 I didn't find that problem. Hi jmulop, I'm so sorry for the problem you encountered.

Calculator App for iPad is a huge market and this is the only Widget one out there! I hope they update soon, they may really have something good here :) Please consider updating the Widget as a paid App I strongly believe the developer should stay on top of these updates. The calculator’s buttons are not visible to use. I’m not sure why the other reviews are so positive… I can only assume the app at one time worked properly as a widget but after an iOS software update (likely 14.7 of 14.7.1) something happened and now the widget cannot be moved or used. You can also configure it to RPN mode, which I prefer. Very frustrating, the calculator doesn’t work.99¢ gone to another unusable app. The latest PCalc update no longer has a widget (control center), but DOES have a nice menu bar icon which is great for accessing the calculator quickly.

Calculator for mac widget