Facebook app still an iPhone battery hog, testing shows

During informal testing, an iPhone 6s Plus saw an average of 15 percent more life with the app uninstalled, according to The Guardian. The paper instead accessed Facebook's website through the iPhone's built-in Safari browser, while leaving Facebook Messenger intact. Testing spanned two weeks — one with the Facebook app installed and a second with it removed.

Similar results were recorded by other recruited iPhone owners, The Guardian noted.

For the main test, deleting the app is also said to have had the benefit of recovering some 500 megabytes of storage, including 111 megabytes from the app itself and the remainder in cache space.

Facebook's main iOS and Android apps have repeatedly been accused of consuming too much battery life, principally by operating in the background when they're not needed. When the issue came to a head in 2015, Facebook blamed the situation on bugs that were later corrected, but The Guardian's results suggest that fundamental problems remain or have resurfaced.

Battery life remains a concern with iPhones. The 6 Plus and 6s Plus can last a full day or more on a single charge — owing to larger batteries — but 4- and 4.7-inch iPhones are often close to empty by nightfall, and sometimes need midday top-ups, particularly if they're used for video, games, or GPS. Apple itself recently put out an official battery case for the iPhone 6 and 6s.