You can download Smart Hide Calculator on Google Play Store
While the above applications can encrypt or hide data, this application goes a step further in terms of safety. When you open the application, the application itself is passed through a fully functional calculator.
When you first open the application, you asked to introduce a number on the calculator screen: this will act as a password from now. To access our data, all we need do is write this number and press the "Like" button (=).
This is basically the same as entering a password otherwise, but an attacker could guess the PIN because the application does not limit the number of attempts that can be made.
We can block all kinds of data formats, but administrator privileges (root) are needed to get the most out of this application.