Verizon does say that a 1 rating means the app will use more than 10% of a 1 GB data plan in a month if running in the background.
For battery life, a 1 means that the app's drain on the battery exceeds more than 20mA, or more than two hours of lost battery life with the app running the background.
A 1 rating for security describes a "critical security threat to user. Harmful impact to device performance and content. App will cause irreparable damage to the device."
Verizon has no app reviews or high risk apps listing for any other app store, including App Store apps that run on iPhone or iPad.
Verizon is evaluating whether it will expand app reviews and high risk apps listings to App Store or other application storefronts, but started with Android partly because Verizon sells so many Android devices, said David Samberg, a Verizon spokesman.
Samberg authored a description of Verizon's reviews on a blog post last week, although the reviews have been underway since last fall.
None of the high risk apps are blocked for Verizon customers, Samberg said, but users are being educated to make their own decisions. "We're not trying to embarrass anybody," he said. "We don't want to block apps; we're saying download, but be aware."
Verizon also posts a listing of the Top 20 must-have apps for for both Google and Apple apps. The list is updated four times a year and currently includes AppLuvr to help people pick apps among the more than 700,000 app on each of the stores.
Productivity apps like Dropbox, Evernote and Smart Business Forms are included on the current Top 20 list.
The value of a 20 must-have apps list is that "customers don't know where to start when they have a new phone," Samberg said. "There are so many apps out there."
Many apps like Facebook are "extremely obvious" and therefore not included, but many others are not. All 20 of the must-have apps have received a rating of 4 stars or above, he said.
Reaction to Verizon's apps evalutions has been positive, he said. "People appreciate it," he said.
And so far, developers haven't objected to the high risk Android apps listings either, he said.
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