The first reviews of Amazon’s Fire Phone are in, and the technorati are not impressed.

The poor critical reception is a signal that the e-commerce company will face even higher hurdles than previously expected in attempting to challenge Apple’s iPhone, Samsung Electronics’ Android smartphones and other incumbent players.

Reviewers cited the Fire Phone’s limited battery life, absence of key apps, lack of features available in rival products, its ungainly industrial design, and the fact that it works only with AT&T.

In unveiling the smartphone, Amazon touted whizzy new features as delivering a new “immersive” smartphone experience. Those include Dynamic Perspective, a system that uses four cameras to detect where the user is looking to render 3D-like perspectives and gesture controls, and Firefly, which can identify some 100 million items, including songs, movies, TV shows and products (sold by Amazon) using different sensors.

But critics found those gimmicky and not very practical. The phone’s “big new features (were) less useful than I expected, and sometimes outright frustrating,” wrote Re/code’s Walt Mossberg. The Firefly auto-recognition was inconsistent, and navigating using Dynamic Perspective was more difficult than simply swiping the phone, he said.

SEE ALSO: Amazon Unveils Fire Phone, in Bid to Challenge Apple’s iPhone

In addition, the Amazon Fire Phone lacks some key functions both Apple and Samsung smarphones offer, including a fingerprint reader and integrated video calling, Mossberg noted. And while Amazon offers 185,000 apps for the Fire Phone, that’s less than 20% of the apps that run on Apple and Android phones, and doesn’t currently have apps such as YouTube and Google Maps.

The biggest problem with the Amazon Fire Phone was battery life, according to The Wall Street Journal’s Geoffrey Fowler, who noted that like the iPhone the battery cannot be replaced.

“In the past five days, I couldn’t once get the Fire’s battery to last to day’s end — a telephonic cardinal sin,” he wrote. In a battery “torture test” streaming video over Wi-Fi with the screen at 50%, the Fire lasted just 6 hours and 40 minutes, 16% less than the Samsung Galaxy and 25% less than the iPhone, according to Fowler.

Other reviewers also found the smartphone’s hardware performance wanting. “The quad-core Qualcomm Snapdragon 800 processor struggles to respond, battery life sputters out quicker than I’d like, and the phone also throws off enough heat to melt a pat of butter,” CNet’s Jessica Dolcourt said.

Critics also took issue with the Amazon Fire Phone’s design: “It’s a study in ruthless efficiency, without regard for anything so immeasurably subjective as ‘beauty,'” said The Verge’s David Pierce, calling it “a dense black slab” that leaves the impression that the Fire Phone “was well-conceived but never quite perfected.”

Not everyone hated the Fire Phone. The New York Times’ Farhad Manjoo called it “uncommonly friendly and easy to use.”

“As a bare-bones smartphone, it should prove especially attractive to people who find themselves overwhelmed by today’s crop of do-it-all superphones,” Manjoo wrote. “When you forget about its whiz-bang marketing, the Fire begins to stand out as something much more interesting: a phone for the rest of us.”

And consuming media on the Fire Phone is “a better experience than what you get on other platforms,” wrote TechCrunch’s Kyle Russell. People who buy all their digital content from Amazon or subscribe to Prime — which offers unlimited access to libraries of video titles and songs — “might find that the Fire Phone is perfectly capable of meeting all of their needs,” he said. Movies and books are treated as apps on the home screen, and Prime members can download TV episodes for offline viewing.

The Fire Phone is slated to start shipping July 25, exclusively through AT&T, in two configurations: a model with 32 GB of storage for $199.99 and a 64 GB model at $299.99 (both with a two-year contract). Without a contract, the phones are $649 and $749, respectively.