lowest cost microcontroller with adc
Well, there is at least one more parameter very important, HOW MANY of them?
If you are looking for 1, 10 or 100, you selection will be extremely limited, if you are looking for 100k there will be some options for you @ 50cent or below. To have at least 10 I/Os you need a 14-pin package.
You could have a look at the low end Silabs devices with 10-bit ADC, they run @ approx. 89cents when you buy 100
**broken link removed**
Just a thought and I hope it helps, Bob