There are already many calculator apps ...

You have to stand out from the crowd. Here is 3D plotting, matrix, solve equations, offer a currency converter and a periodic table.
I'll start with the periodic table. The program displays a photo of the current periodic table of elements in English from the side [...]. This has now not so blew me away. One could, for example, the individual elements can make playable and display detailed information. For example, a model of the atomic nucleus or so. That would have been cool. Well, there is still the other features.

The 3D viewer works very well. But I do not understand why this has to rotate without I express what. It would be nicer if it only turns when I put it in an axial direction. But the possibility itself is really cool.

The currency converter is in my opinion the most useful feature. Here, the appropriate flag is displayed for each currency and if I enter an amount above, the matching amount in the relevant currency will appear in the list. I always wanted to know how many Malaysian Ringgits I would get for 50 euros in my wallet. Joking aside. The courses are current and the feature is useful.

Matrix works, but the presentation Dislikes personal way.

We are already at my main criticism: The UI. It just does not look good. In landscape mode on the Kindle, the keys are only half visible in the far right row. That irritates and should be resolved in any case by update.

Wen, the UI does not disturb the can here like to strike. I will, however, remain at Mathapps.
If the developer at UI nachlegt and perhaps offers some nice features to the periodic table I'd like to assign more stars.

Oh yes. And a German localization would not be so bad.