OReilly has a book "Building iPhone and iPad Electronic Projects Real-World Arduino, Sensor, and Bluetooth Low Energy Apps in techBASIC" http://shop.oreilly.com/product/0636920029281.do

you can learn about techBASIC at http://www.byteworks.us/Byte_Works/techBASIC.html

they claim on their website that techBASIC apps can be sold through Apple.