SSLDroid is a free, Java-based plain-to-SSL proxy for Android devices developed by PLBC. It is designed to provide client-side certificate-based authentication capabilities to software on Android, particularly email and calendar sync applications. This program is similar to stunnel and aims to secure Android devices by allowing them to communicate with SSL/TLS-enabled servers.

One of the main features of SSLDroid is its ability to provide secure communication by acting as a proxy between the Android device and the server. It can encrypt and decrypt all traffic between the two endpoints, allowing for secure data transmission. Additionally, SSLDroid is entirely Java-based, making it easy to install and use on any Android device.

Overall, SSLDroid is a reliable and straightforward SSL proxy that can enhance the security of Android devices. Its primary focus on client-side certificate-based authentication sets it apart from other SSL proxies and makes it a valuable tool for those looking to secure their Android devices.