They support Java 7 syntax, however they do not have the API improvements in Java 7. For example, Java 7 introduced a much improved File IO API in the java.nio.file package. It has very useful classes like Files (http://docs.oracle.com/javase/7/docs/api/java/nio/file/Files...)

Android does not have any of this (http://developer.android.com/reference/packages.html) because the Apache Harmony project died before it could implement Java 7 API changes.

This is a much bigger issue for Java 8. Just supporting only Java 8 syntax changes greatly reduces the benefits of the new lambda and default methods. Much of the power of the changes, especially lambda, require the changes to the collections API.