How much information do they have on their users and what are the business alternatives for these companies?

They have a wealth of demographic information on their users.

"One of the things we're concerned about is the effect this could have on regular wireless users."

The client has no reason to spy on users like this.

Companies don't just save all this data on users so they can claim the largest database.

And I think, you know, we put - there's a huge burden on users to be security experts, to protect themselves.

The company is "relying on users to monitor each other," he said.

Others said the ads might sometimes grate on users, but they were a price of free, quality financial information.

This means that developers can rely on their users having it.