Would you like a milkshake with:
Chocolate bar
Cake
Biscuits
Cereal
etc

Would you like anything else with it?
(note - if it was Shakeaway then a mobile web form would be totally inappropriate because there are hundreds of combinations)
Strawberry
Cherry
Lime
Kiwi
Melon
etc

Dairy or alternative?
Dairy
Soya

Any extras?
No thanks
Extra icecream
bran
protein
etc

Finished?
Yes
No

Would you like to save this as a favourite?
Yes
No

All of the above could also branch out - imagine if you were standing at the counter and being asked what you wanted, with lots of choices to look at, you might need several decisions or you might have a favourite - mine is chocolate & cherry with soya - so on the form I would be saying chocolate then selecting cherry then soya, no thanks then yes to finish. However if you would like anything else (question 2) you could potentially have additional sub branches e.g. 2a being lists of chocolate bars, 2b being cake options etc etc, depending on how many flavours you wanted. 

In voicexml forms, each question would be treated as its own ‘block’ so you would need to add in extra code to tell the form to go to other blocks. No idea exactly at this point how to code the cookie bit (i.e. would you like to save as a favourite, am assuming that you can save cookies on a form on mobile device in same way as pc, but haven’t looked into as yet), but it would be useful seeing as you are using a phone and want to save time being online.