So I read this article on Mobile Orchard and, as I\'m planning on having my first steps in Android development, it got me thinking: is it possible to develop for Android in Lua
I know this is an older question, but just to correct some misinformation (in the comments) for people who come later, Corona SDK (as of spring 2013) has a Starter Edition which is free -- no splash screen or anything. The main difference between it and the "Pro" version is you can't do in-app purchases in the Starter Edition. But you can use it to create apps for sale, etc. No expiration date on it or anything.
And in answer to the original question, learning Java may allow you to write Android apps, but if you then also want to target iOS you don't have any great options. By choosing something that's cross-platform from the beginning you can target Android or iOS or both. Lua (in any of the flavors already mentioned) is a great base language to learn for mobile development.