I'm fairly new to encryption, and I am investigating the different kind of encryptions. I want to encrypt passwords in a secure way. I discussed this with my colleague, and he said that BCrypt is the best encryption for our project. We have a PHP server, Android client, and iOS client as our setup.
I am using a jBCrypt implementation for Android, and an Objective-C port of jBCrypt for iOS. My colleague is making the PHP server and he is using crypt_blowfish. He found out that the PHP implementation of $2a$ is insecure, and asked if I could use $2y$.
But I cannot find any $2y$ implementations of jBCrypt. Are these different versions compatible with each other? Is it secure to use $2a$? If it is not, is it hard to make a $2y$ version myself?
Thanks in advance