I've seen a lot of iPhone and iPad giveaways on Facebook as well. Apparently, they'd ask you to like the page or post, pick a color and comment it under and share it on your wall to qualify. I never really believed in it and thought about it simply as a way to monetize the ad by likes, comments and shares. We have not really found out if anyone had actually won and they usually get away with fooling people because everybody knows that as long as there are many participants, the chances of winning are slim but they join anyway.
Well I have to agree with @maxen57 and there always too many strings attached and you know that they are trying to benefit from it, which is fine, but it does not do much for my excitement levels. Anytime I am asked to give personal information or post for them or things like that, it turns me off to the whole idea and the giveaway or whatever it happens to be. Also, like @Denis Hard said, there are a lot of scammers out there too, so that never helps.
I'm careful which contests and sweepstakes I enter. Check to see if the company or organization hosting the campaign is a legitimate one. Sometimes they will even fudge the name of the organization, changing the spelling slightly, so at first it appears to be legitimate, but upon inspection, there are usually clues that it's a scam. I fell for a few of the ones mentioned such as 'we're giving away a new Mercedes' or large amounts of money when I first started on the site (Facebook), but have since learned to ignore them. I have a Facebook friend who enters and reposts a lot of those types of events, and hers is the account that is always being hacked, and that's probably why.
I have usually ignored many offers since I've never heard of anybody who has ever really won any prize. It is a way of cheating users so that one can advertise whatever he wanted to advertise. Most of this offers are intended to collect your email address so that they may be sending you advertisements. I think that we should all ignore them.
Yes, some of those contests and so forth, are just scams to get you to post info about the company. Sometimes even legitimate companies do that, it just ends up being a waste of time. Sometimes, on Facebook coupons will be offered and those are usually legitimate but free gadgets and the like,,,I don't know anyone who has got one.
Most of the time competitions on either Facebook or Twitter are fake. Unless they're a big company like Amazon or Game doing a competition don't bother entering or even trying as they are just there to get more likes and exposure. I've retweeted a few game giveaways on Twitter and most of the time those posts just get deleted after they get a lot of followers. Of course I unfollow them straight away.
I always see iPhone and other gadget giveaway on facebook and I also see many of my friends liking the post/page and leaving a comment just because the lucky winner will have an iPHone or other gadgets. I don't think this is real. I am almost 100 percent sure that this is just a way to trick people to like page/post. Unless the contest is organized by the company that produces these gadgets, this kind of free giveaway is fake.
I have faced it on many websites including Swagbucks. They start the campaign offering freebies but a participant always ends up registering on a shopping site and doing some purchasing. I have stopped heeding to all such fake offers for a long time.