I found a post from a while ago that addresses a similar question but I think it's a bit outdated. I realize implementations of JPA tend to be more on the heavy/dense side, so if you know of any lightweight (non-JPA) ORMs I'll most certainly appreciate your input. I did see the answer about ActiveAndroid in the other post and am curious to know if anyone tried it out.
Update:
In the end, I decided to go with a more lightweight solution and chose DB4O. So far I've been very happy with my choice. It's extremely easy to use and requires a minimal amount of configuration. The website contains a wealth of information including sample projects and an in-depth tutorial that covers just about everything a developer might need to know about DB4O. Oh, and did I mention that it's free (unlike some other alternatives... coughActiveDroidcough)?