So I wanted to test my luck with one of those ipad giveaways.
Traffic source: Airpush, CPC 1c
Offer: WAP Czech Republic Win an iPad, $4.10/CPL
Lander: Pinnion.com Survey
Offer LP:

Direct linking to the offer gave me:
$8 Rev, $5 exp, $3 profit, 500 clicks, 2 leads
After speaking with my AM, he kept saying all of the affiliates on the network are running LP's, and this would increase my CVR. Furthermore, 1c traffic only drips in, and at 2cents, I would be at a loss, so an LP is required to pre-sell.
So, I made a survey:

Intro, 3 questions, Congrats page
Intro:
Answer this short quiz to win!
We only have 3 left. Hurry!
Tap Begin Now
Questions:
1. who is the current prez of Czech: Havel, Zeman, Klaus (used wikipedia)
2. What country is neighbors with Czech: Germany, France, Spain (CIA fact book)
3. Who introduced the ipad in 2010: obvious
Congrats + Link
Congratulations!
You qualify to win a new ipad!
--> Click Here Now <--
Ran some more traffic, and got this from the pinnion Survey:

As you can see, the 'mobile' version of the survey converts well, while the web version dies off.
Looking at the 'clicks out' stats, I don't see a correlation in what phones have a good LP CTR.
(using Airpush's tokens: %device%, %manufacturer%, etc)

Some research into this (I don't know if airpush has %OS version tokens), reveals that CTR's happen on Android 2.3+. But I would need more stats on this.
No conversions yet, but clearly there are certain phones that work better with pinnion than others.
/food for thought.
Your lander/angle should work (check with your network if its okay - you might need to change the wording slightly)
Airpush = Android traffic
Start by optimizing carriers, bid higher and get a lot more traffic before making decisions
So I've decided to pause this survey method because the platform, www.pinnion.com, doesn't seem to support mobile too well.

As you can see, lots of the mobile traffic is being directed to the 'web' version, which doesn't work on the survey.
But the survey itself works quite well. 40% of visitors complete the survey.
Here are the stats for the Android 2.3+ only traffic, Clicks, and click-throughs

So 40% of users (who saw the actual survey) completed the survey.
Also, 60% that completed the survey, also went to the offer LP.
So, if my math isn't that terrible, we have a 24% LP CTR with this survey.
Here is some carrier data for CTR's.

For the time being, I have a small list of devices that work with this survey platform, but that doesn't mean these devices convert.
Gonna try survey monkey, or another mobile survey platform.
Things to also try: post-popup, google analytics tracking
You could always make a survey style lander yourself using jQuery mobile. Then you wouldn't need to worry about users being redirect to the web version and you can make it so every answer is correct
.

Keep running till you see conversions, then cut the total junk
Mobile costs a fair bit in beginning testing
Anyone know which is more effective... a survey or a quiz?
Surveys have worked better for on mobile for me. I'm guessing because they look more serious, and bring a certain level of trust in contrast to quizzes.
After looking over your lander I'd recommend restructuring your lander to make people feel more like they deserved to win the iPad. Would you be suspicious about winning an iPad after 3 piss easy questions? Make three tests, a easy quiz, medium quiz, and a hard quiz. That should give you some interesting data to play with.