Systems and methods for improving the restrictiveness on accessing software applications on mobile devices, such as cell phones, are disclosed. In accordance with an exemplary embodiment, a computer-implemented system and method for improving the restrictiveness on accessing software applications comprises using a device having a memory, wherein the software application is stored in the memory and requesting, from the user, an original PIN, wherein the original PIN is not stored in the memory and any information about the original PIN is not stored in the memory. The invention further comprises using the original PIN as a seed number to create a true encryption key, using the true encryption key to encrypt an application secret data into a ciphertext and storing, in the memory, the ciphertext. The invention further comprises requesting a PIN from an accessing person that is accessing the targeted software application, wherein the requested PIN is not validated by the software application, using the requested PIN, without any validation, as the seed number to create an encryption key, and using the encryption key to decrypt the ciphertext.