In the past, I've written some about ways to earn with your smartphone. IdeaShifters is a mobile phone survey panel that you can use to do that. Basically, you are just answering surveys for them with your smartphone.
How does IdeaShifters pay?
IdeaShifters pays in points, but you can redeem these for things like Amazon gift cards. In my opinion, that's always a good thing since I know I'll use these for Christmas, birthdays, and so forth.
What kind of phone do you need to use IdeaShifters?
When you sign up, they ask if you are using an iPhone, Android, Blackberry, or a Windows-based smartphone as well as a few others. So hopefully this is going to be compatible with several different phones although I think in the past it was only available for Apple users.
Who can sign up?
Right now it's for US only. Maybe in the future they will change this though.
Do they have a referral program?
They do, but I am unclear on how you benefit from referring your friends to use the app.
Are there any other perks?
If you sign up IdeaShifters will go ahead and credit your account with 10 points. Also, I think that taking surveys via your smartphone is a great idea! You can do it when you're bored or if you're not at home and just killing time in a waiting room or something. The points will add up over time and then you can claim a reward.
Signing up is simple, they only ask you a couple of questions. If you want to start taking surveys in your downtime for this company, you can go here.