Spongy Castle is a repackage of Bouncy Castle for Android (which ships a crippled version of BC).
Spongy Castle is the stock Bouncy Castle libraries with a couple of small changes to make it work on Android:
- all package names have been moved from org.bouncycastle.* to org.spongycastle.* - to avoid classloader conflicts
- the Java Security API Provider name is now SC rather than BC
- no class names change, so the BouncyCastleProvider class remains Bouncy, not Spongy, but moves to the org.spongycastle.jce.provider package.
SDK for Android
This release is now available on Maven Central, based on Bouncy Castle r1rv54 - note that the Bouncy Castle release notes include a TLS 1.2-related security advisory for CVE-2015-7575 - see also the BC mailing list announcement.