Not much 'like' for Facebook mobile apps

What investors care about more than user ratings is that consumers continue to join the service and those that are signed on keep coming back, said Aaron Kessler, an analyst at Raymond James in San Francisco.

'It's engagement that matters,' said Kessler, who has the equivalent of a 'buy' rating on the stock. 'Engagement has been strong this year.'

In the third quarter, Facebook had 864 million daily active users worldwide, up from 829 million in the prior period. Mobile accounted for the bulk of that, with the number of users increasing to 703 million from 654 million. This from a company that just two years ago was watching its stock price plunge on concern that it wouldn't be able to transition its business from the Web to smartphones.

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So how much do consumer reviews matter? Unlike many lesser-known apps, Facebook's ubiquity means that it doesn't need promotion in the app stores to get discovered and generate downloads. And people want to be where their friends are, making Facebook a difficult place to leave.

But there could very well be future repercussions to testing the patience of users. The younger generation is already shifting to services like Snapchat (3.4 stars on iOS, 4.1 on Android). New social apps are popping up by the day with a focus on mobile design and simplicity, so Facebook's long-term dominance can hardly be taken for granted.

One particularly thorny issue is that in order to please shareholders, Facebook has to boost ad sales, which requires thrusting more promotions on to small screens. Should annoying ads start to push consumers away, marketers will find other places to spend their dollars.

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'If consumers aren't delighted by the experience, does that flow over to their receptivity to advertising?' said Dan Slivjanovski, a senior vice president at Web advertising company Blinkx. 'That's a logical question.'

It's not happening yet. According to eMarketer, Facebook will capture 68 percent of ad spending on social networks in 2014 as well as in each of the next two years.

A Facebook spokesperson declined to comment.

In previous versions, Facebook has rated better with consumers. According to App Annie, the average rating for all versions of the main iOS app is 3.7 stars and for Messenger is 3.2.

While the latest iterations face a barrage of criticism, the mobile companies acquired by Facebook have created some of the most beloved apps on the market. Instagram, the photo app that Facebook bought in 2012 for close to $1 billion, gets 4.2 stars on iOS and 4.5 on Android. WhatsApp, the messaging service that cost Facebook $19 billion this year, is rated 3.9 on iOS and 4.4 on Android.