NAT via iptables - Won't work!!

Hi guys

I'm running on debian on a small embedded system. I have a ppp interface that is connected to the internet (and works). My unit also has wifi access point (which works and I can connect to it).

I want to allow connections to the wifi to be able to use the internet from ppp0 interface. So basically want to set up a router type system.
right now, when I connect to my device with my phone, I cannot use the wifi. But on the shell of the embedded system, I can ping, I can load pages, i can do all sorts of things.

Here is what I have set up for my IPtables:

But i still can't browse internet on my phone.

Any ideas?

Thanks!

Am I

To do routing, you'll probably want to either set up routing (not the same as iptables), or bridge the two interfaces into one pseudo-interface (also not the same thing as iptables).