Payday loans get a bad rap, and deservedly so. Their interest rates and fees are very, very high. But if you absolutely must take out a payday loan, do so at a local store, not online. If you've taken out a payday loan from your local payday lender and you fall behind, they will call you--a lot. You'll be annoyed by how aggressively they will try to collect from you. They might even call people you listed as references. But if they step over the line into illegal collection actions, you can do something about it. You know where they are located, and with the help of a lawyer, you can get them to stop.
If you apply for a payday loan online, you are sending out a lot of very personal information to companies that may not be trustworthy. Some times, the website you apply to is just in the business of selling "leads" to other companies. That means your info is now all over. I've heard from many people about how these companies will act illegally in trying to collect their debts. Some people end up getting calls saying they owe money that they never borrowed in the first place. Other clients have told me that the online lenders will call and threaten outrageous things, telling them they are going to jail unless they pay. This is untrue, but there's usually not much to do about it. Even with the help of a lawyer, online payday lenders are often impossible to find or lare ocated outside of the U.S. That means it's hard to enforce any kind of action against them.
Bottom line: avoid payday loans at all costs. But if you absolutely must, apply in person, not online.