That's changed recently. But it has nothing to do with the controversy over the photo-sharing services's new, ad-friendly terms of service.
What has users upset, according to Appsfire, an app-rating service, are changes to its basic operations in an update rolled out a week ago.
Instagram made it harder to crop photos and import photos already stored on your phone, generating more than 6,000 one- or two-star reviews.
That sent Instagram's quality score, as calculated by Appsfire, plunging from 97 to 11. (100 is the max score.)
Despite the fuss in the media, most users—Tiffani Amber Thiessen excepted—don't care about privacy or advertising. Instagram photos are already public by default, and most users don't make their photos private.
What they do care about is being able to quickly and easily share their photos without having to go through a lot of extra steps. The clunkiness of mobile photo sharing on Flickr, Twitter, and Facebook's older apps created the opening for Instagram to grow to 100 million users.
Tinkering with the core photo-sharing experience is where Instagram can make itself vulnerable. And where the ads controversy can hurt Instagram is if the team working on it gets distracted from fixing the app.
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