I'll be brief as a lot more will most likely be written elsewhere. See a good thread of points tweeted throughout the day at @bigmconf.
App distribution and monetisation - the only things more important than lines of code - Raam Thakrar @raamthakrar
Raam Thakrar was a great opener. It really got your attention in being outspoken and forthright. What was surprising was his view on Boris Bikes. A user base built on a subset of Londoners where at best you'd get 50k users and you're more likely to be only reaching 10k users. That's not worth the effort as it's not going to make you enough money. Wow.
Another astounding moment was when he asserted that devs need to be paid the right amount of money. He calls around £50k an appropriate amount for good devs!
My favourite moment, perhaps of the day, was when A Man From Orange asked "How do you advise we make our app store better?" to which Raam replied "Forget your app store, enable payments". The Man From Orange claimed "We're doing that, mostly in NFC". Then Raam retorted "I'm sorry, but I just don't believe you!". I don't either. I suffer the Orange website as a customer, and payments is the one thing that just hardly seems to work (apart from on the online shop when buying a new mobile, funnily enough).
Beyond Usability on Mobile - Aral Balkan @aral
Aral Balkan presented by far and away the best talk of the day. The most inspiring, the most entertaining, the most laughs. I just loved what Aral had to say, and how he put that into practise in his Feathers app (which I'm going to buy - and review!). His passion for making things magical. That really is something else. It made me want to attend his workshop today on iPhone design principals. Maybe another time.
Future Innovations in Mobile - Paul Golding @pgolding
It was about this time last year that I saw Paul Golding speak at the Eduserv Symposium on Mobile, and I was really impressed then. More so this year as you could see that he'd kept on top of trends. Not much of what he covered last year was in his talk yesterday..
Really good talks I really enjoyed these. The others weren't bad, but these just stood out more from the day.