yourkarma.com, $80
The Karma Hotspot gives you free data each time you allow someone to share your hotspot.
While it appears to be one of those apps that overshares, it isn't.
The Karma Hotspot acts as a go-between to connect a Wi-Fi phone, tablet or computer to the Web using the mobile phone network. It gives away data, too — 100 megabytes' worth — when you sign up, and each time you allow someone to share your hotspot. That 100 megabytes is equivalent to downloading about 300 e-mails or 15 good-quality three-and-a-half-minute songs.
To make joining easy, Karma's registration is through Facebook. All you need is an e-mail address and a Facebook password, and you're in. In fact, you can't currently sign up without a Facebook account. The company said it is working on an alternative.
Here is where the confusion comes in: When you sign up with any app through Facebook, it asks if you want to allow the app — in this case Karma — to share information. If you say yes, you will see a message telling you that Karma can share posts on your timeline. That makes it look as if it will.
But, although the mechanism is there to share, said Robert Gaal, Karma's chief executive officer, the app doesn't send any automatic notifications, so it doesn't matter. In a test, Karma sent no unwanted alerts.
To be doubly sure, you can take another step to protect your privacy in Karma's Facebook settings. Look for the little gear icon in the upper right corner of your Facebook home page. Click it for a drop-down menu, and choose "account settings." Look for the list marked "apps," and click.
Where you see Karma, click on "edit." That should open a list of options, with "Visibility of app" at the top. Click on the drop-down menu there and choose "Only Me."
