Changes introduced included new color options (Matte Black and Jet Black), water and dust resistance, a new capacitive, static home button, revised antenna bands, and the controversial removal of the 3.5 mm headphone jack.

The device's internal hardware received upgrades, including a heterogeneous quad-core system-on-chip with improved system and graphics performance, upgraded 12 megapixel rear-facing cameras with optical image stabilization on all models, and an additional telephoto lens exclusive to the iPhone 7 Plus to provide enhanced (2x) optical zoom capabilities and portrait mode.

Apple's plans to remove the 3.5 mm headphone jack received significant media attention.

[b] Other rumors included a flush camera, stereo speakers,[14] a 256 gigabyte storage option, and a larger 3,100 mAh battery.

[15] On August 29, 2016, invitations to a press event at the Bill Graham Civic Auditorium in San Francisco, California on September 7, 2016, were sent out to members of the media, prompting immediate speculation of the iPhone 7's upcoming announcement.

[43] The adapter is also compatible with other iPhone, iPad, and iPod Touch devices running iOS 10 and newer.

[47] The displays have identical sizes and resolutions to iPhone 6S, but with a wider color gamut[18] and increased brightness.

Many reviews panned the removal of the 3.5 mm headphone jack; some critics argued that the change was meant to bolster licensing of the proprietary Lightning connector and the sales of Apple's own wireless headphone products, and questioned the effects of the change on audio quality.

Apple was also mocked by critics for Phil Schiller's statement that such a drastic change required "courage".

Gordon Kelly of Forbes noted that rival smartphones, such as the Samsung Galaxy S7, had increased battery life and added water resistance over its predecessor while retaining the headphone jack, and that the iPhone 7's camera photo quality was improved but still lagging behind some phones already on the market, including the Galaxy S7 and Nexus 6P.

Kelly praised how Apple was able to extract improved brightness and accurate color reproduction from its LCD display panel, while noting that it was old technology which was also well behind rivals who had already moved to sharper 1080p or even 2K screens.

[70] John McCann of TechRadar wrote that for the first time, the phablet-sized iPhone 7 Plus was "markedly better" than the smaller model.

McCann wrote that the lack of a headphone jack was "initially frustrating", but noted that it was a "positive step forward for the mobile industry", despite the "short-term effects ... making the most noise for now".

[d][73] In a particularly scathing article, Nilay Patel of The Verge wrote that removing the headphone jack, "a deeply established standard" as he put it, would be "user-hostile and stupid".

[70] In particular, Apple's vice president Phil Schiller, who announced the change, was mocked extensively online for stating that removing the headphone jack took 'courage'.

[75][76] An online petition created by the consumer group SumOfUs, that accuses Apple of planned obsolescence and causing substantial electronic waste by removing the headphone jack,[77] reached over 300,000 signatures.

[79] The Daily Telegraph speculates that the iPhone 7's new A10 Fusion processor is the source of the noise, linking to tweets that compare the phone's hissing sound to "hearing the fans spin up loudly whenever your Mac's CPU gets used to its actual potential.

The report concluded with the statement that "We are not sure what was the main reason behind Apple's decision to source two different modem suppliers for the newest iPhone".

[citation needed] In the iPhone 7, Apple added a software lock that prevents individuals from attempting to replace the home button on their own.

[87][88] Some iPhone 7 devices with the model numbers A1660, A1779 and A1780 suffer from a problem where they show a "No service" message even when cellular reception is available.

A few users also complained that lightning EarPods failed to work with the device and that the Wi-Fi button would be grayed out after restarting the iPhone.

If an affected iPhone 7 was no longer covered by warranty, Apple said its service providers could request an exception for this particular issue.

Apple has deliberately withheld pre-order sales numbers, citing that these are "no longer a representative metric for our investors and customers".

[90] Without releasing specific numbers, T-Mobile US stated that the iPhone 7 had broken the carrier's all-time record for first-day pre-order sales.

[93] After customer complaints and a class action lawsuit,[94] Apple made changes to ensure members of the program could get new phones as soon as possible.

The report, "based on data from suppliers", stated that Apple would trim production of the iPhone 7 by 10% in the first quarter of 2017, following "sluggish" sales.