Critics praised Continuity and Extensibility as major features enabling easier control and interaction between different apps and devices.

They also liked the QuickType keyboard word suggestions, and highlighted Spotlight Suggestions for making the iPhone "almost a portable search portal for everything.” However, reviewers noted that the full potential for iOS 8 would only be realized once third-party developers integrated their apps to support new features, particularly widgets in the Notification Center.

In October 2014, it was reported that the adoption rate had "stalled,” only increasing by "a single percentage point" from the previous month.

[5] iOS 8 introduced Continuity, a cross-platform (Mac, iPhone, and iPad) system that enables communication between devices in different product categories.

[6] iOS 8 introduced Spotlight Suggestions, a new search feature that integrates with many websites and services to show more detailed search results, including snippets of Wikipedia articles, local news, quick access to apps installed on the device, iTunes content, movie showtimes, nearby places, and info from various websites.

Spotlight Suggestions are available on the iOS home screen as well as in the Safari web browser search bar.

[18] iOS 8 introduced Family Sharing, which allows up to 6 people to register unique iTunes accounts that are then linked together, with one parent becoming the administrator, controlling the overall experience.

Time-lapse records frames at shorter intervals than normal film frequencies and builds them into movies, showing events in a faster speed.

[30] Additionally, the Photos app gained more precise editing controls, including improved rotation; one-touch auto-enhancement tools; and deeper color adjustments, such as brightness, contrast, exposure, and shadows.

[33] Despite being replaced by a "Recently Added" album, the removal of Camera Roll sparked user complaints,[34] which Apple returned the feature in the iOS 8.1 update.

[39] In the Safari web browser, developers can now add support for Safari Password Sharing, which allows them to share credentials between sites they own and apps they own, potentially cutting down on the number of times users need to type in credentials for their apps and services.

[43] HomeKit serves as a software framework that lets users set up their iPhone to configure, communicate with, and control smart-home appliances.

[46] Equipment manufactured without HomeKit-support can be enabled for use through a "gateway" product, such as a hub that connects between those devices and the HomeKit service.

Brad Molen of Engadget highlighted Continuity as a major advancement for users with multiple Apple devices.

However, Molen noted that some of the new introductions - Family Sharing, Continuity, and iCloud Drive - require further diving into the Apple ecosystem to work.

"[60] Martin Bryant of The Next Web wrote that "The real advances here are yet to come," adding that "Apple has included demonstrations of what can be done, but the true power of what's under the hood will be realized over the coming days, weeks and months" as third-party developers gradually incorporate new features into their apps.

[62] In October 2014, Andrew Cunningham of Ars Technica reported that iOS 8 user adoption rate had "stalled," only climbing "a single percentage point" since the previous September measurement of 46%.

"[63] In December, a new report from Ars Technica stated that iOS 8 usage had increased to 63%, up "a solid 16 percent.

[65] In September 2014, the iOS 8.0.1 update caused significant issues with Touch ID on iPhone 6 and cellular network connectivity on some models.

Apple stated that affected users should reinstall the initial iOS 8 release until version 8.0.2 was ready.

[73][74][75] The bug, named "effective power,"[76][77] could potentially continuously reboot a device if the message was visible on the lock screen.

In September 2014, a hoax Apple advertisement for an alleged feature of iOS 8 called "Wave" circulated on Twitter, which promised users that they would be able to recharge their iPhone by heating it in a microwave oven.

This feature did not exist, and the media cited numerous people reporting on Twitter that they had destroyed their iPhones by following the procedure described in the advertisement.