Apple recently launched its new-generation iPhone 6 and iPhone 6 Plus, both of which sport battery improvements over their predecessors, but just how good are their respective batteries?

Both the iPhone 6 and the iPhone 6 Plus have drawn lots of attention and they are among the hottest devices currently available on the market. As always with highly-anticipated devices, expectations are high and it remains to be seen whether the handsets will measure up.

Right on launch day, the folks over at iFixit got their hands on both the iPhone 6 and the iPhone 6 Plus and tore them apart in their famous teardowns, revealing notable improvements over the iPhone 5S in the battery department.

The iPhone 6 packs a 1,810 mAh battery and the iPhone 6 Plus packs a larger 2,915 mAh unit. In other words, the iPhone 6 Plus' battery is significantly larger than that of the iPhone 5S, while the iPhone 6's unit is only 300 mAh more powerful.

At the same time, battery size is not everything, as it's also very important for the battery unit to be efficient and for the device itself to properly manage and conserve battery life. A new report from Phone Arena now reveals more specific details about the two new iPhones' battery performance.

"For most Apple fans, the iPhone, irrespective of the generation, is above reproach. And in our experience, this is justified for a very big part. But the latest iPhones, including the new iPhone 6 and iPhone 6 Plus, have a very specific and undeniable weakness when compared with what competitors offer, and that weakness is battery life," Phone Arena reports.

"As usual, we put the two aforementioned iPhones through our custom battery life test, which attempts to estimate how long the average person will be able to use a given device if he doesn't put it down at all."

After this test, Phone Arena found the iPhone 6's performance underwhelming, especially when compared to some of its Android rivals. The iPhone 6 lasted for 5 hours and 22 minutes, compared to the 7 hours and 38 minutes from the Samsung Galaxy S5, and the whopping 9 hours and 29 minutes of the newly-announced Sony Xperia Z3. The iPhone 6 is thinner than both the Galaxy S5 and the Xperia Z3, but, as Phone Arena further points out, not all would happily agree to this trade-off.

The iPhone 6 Plus, meanwhile, is better in this department, and scored 6 hours and 23 minutes in Phone Arena's test. In several cases, this is a better performance than for other 5.5-inchers out there. The LG G3, for instance, scored 6 hours and 14 minutes in the same test, while the OPPO Find 7a scored 6 hours and 6 minutes. Other Android flagships perform even better, but the iPhone 6 Plus nonetheless holds its own.

As per Phone Arena's chart, the iPhone 6 Plus grabs the fifth spot, trailing the Sony Xperia Z3, the Huawei Ascend Mate 7, the Samsung Galaxy S5, and the HTC One M8. The iPhone 6 ranks lower on the ninth spot, trailing the LG G3, the Galaxy Note 3, the new Moto X, and others.