[quote name='McCHitman']Are these sites legit? If so, how do they work and are they really worth it?[/QUOTE]
You dont know if you dont check them out but they are legit

cuz I have earned at least $20 for giftcards. You just download these apps, more the better cuz sometimes they offers same apps, so you download 1 offered apps and can earn points for all of them.
Lets say: Hotels.com apps offer appears on all of these sites, you open the link to download this apps on all these sites, then you download it, open for 30s or a bit longer, then close, delete it whatever and you get points for all sites that you opened the apps from. Here is the points-system breakdown:
Sites Points/apps
Freemyapps 50-300p or even more
FeaturePoints 74-800p - 800 is for review paid apps.
Freeappslots 4 spins
Appbounty 90p
There are more of sites like these but I just like these, you can find out more by google yourself.
P.S just after I posted this, freemyapps offered an offer for 240p

Here I go my $10 Itunes GC.