JNCryptor is a Java library that simplifies encrypting data with AES. The corresponding library for iOS is RNCryptor.
JNCryptor is a Java library that simplifies the process of encrypting data securely using AES.
JNCryptor is based on the RNCryptor library for iOS. Both libraries use a common output format, allowing sharing of encrypted data between Java (hence, Android) and iOS applications.
Implementations are available in other languages too, see the RNCryptor project page for more details.