It comes down to why people buy your app. If a lite version is going to give them a chance to experience why they would want to use the full version without alienating them, then go for it.<p>But don't think of the reduced version as a crippled version, think of it as one that gives the flavour of what the full app should be with some obvious disadvantages. For instance, if your app lets someone produce images and email them, the lite version should let them produce images and email them, but put a "produced by App Lite version" watermark on rather than disabling email functionality.<p>That way they can see exactly what the advantage of upgrading is, without being restricted from using all the features.