All smartphone batteries degrade over time so it is not unusual for Apple to be slowing down the performance of its older phones to help prolong their battery life, according to experts.
But some owners prefer faster performance.
They were reacting to Apple's statement on Wednesday - in response to a claim by an app company earlier this week - that it had introduced a software feature last year to prevent phones from unexpectedly shutting down.
Apple said the move was meant to reduce power demands, which can have the effect of slowing the processor, when a phone's battery is having trouble supplying the peak current that the processor demands.
Currently, affected models are iPhone 7, iPhone 6, iPhone 6s and iPhone SE, with other models potentially receiving the same feature in the future.
Professor Subodh Mhaisalkar, executive director of the Energy Research Institute at Nanyang Technological University, said that rather than goading iPhone users to upgrade by making their older phones slower, Apple's move in fact helped consumers by allowing batteries to be used for a longer period.
"(But) it is a trade-off. When your battery is degrading, you have the choice of either living with a slightly slower operation of the phone, or changing the battery," he said.
Some iPhone users, who said they would prefer a faster phone, wanted Apple to be more transparent with the effects of its updates. - LIM MIN ZHANG
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