The mobile clients can either use the same Java version as the Ignition server or it might be necessary to set a specific path to the Java version that you want the mobile clients to access. A likely scenario for this is if the Ignition server is upgraded to run on Java 9 but the underlying technology that the Mobile client uses to run can be limited to Java 8 pending technological upgrades in the future. Regardless, setting the Java path will result in more control over which version of Java runs the mobile clients. The settings take either the system path such as Java or a full path to the java.exe file.