Anvil: big progress for a small library I have just released Anvil 0.0.2. So many changes have been made and now I am absolutely confident that Anvil has its strong points even though I’m the only active user of it. What is Anvil? This section is for those who missed the early steps of Anvil. Anvil is a tiny reactive UI library for Android. What does this mean? It means that you can declare your UI in Java, bind your data to the views, bind event listeners to the views and leave it running.