What is the fine-grained topic of the following text: However, discerning Android users who want to get a first-hand experience of Android 5.0 ahead of its official release, can go ahead and install the CM12 Alpha build for Lollipop on their device, with due credit to XDA Senior Members, SeannyM and Alberto97. Only return the topic.
Installing the CM12 Alpha build for Android 5.0 Lollipop