Check it out at http://www.revmentor.com
For those new to Rev like me, he has some great videos that explain various app design concepts very clearly, so that even a code noob like me can understand them.
For those who are further along, RevMentor has other materials that would be useful.
There's a very modest monthly fee for subscribing to the site. So far, I can see that I'll get much more value out of the site than the fee.
Jerry also offers private one-on-one mentorials to help you with app development issues you're dealing with, etc. Of course, there's a fee for this, but considering what he offers it's very reasonable.
Highly recommend that you check RevMentor out!
