Many other theories suggested that Apple slows down old devices to encourage customers to get new iPhones. To speedup your phone faster, one can replace its battery. It will cost $79 from Apple and its considered to be cheaper method rather then buying new phone.

Benchmark Data Reveals Apple is Slowing Down iPhones with Old Batteries

Geekbench is one of the most commonly used iOS speed tests, so John Poole, its developer, pulled the data. The test showed a big peak which means iPhone was running at its full strength.  But it was also observed that benchmark distribution of iPhone 6, iPhone 6S and iPhone 7 units running any version of iOS newer than 10.2.1 had multiple peaks. It means a software limitation was restricting some devices due to slower processor speed. Older phones had more prominent peaks. Here’s the distribution he found for the iPhone 6S:   Hence it is confirmed that Apple is slowing down the processor on phones with old batteries may be to boost its performance. However may be people are right that Apple is slowing down processors intentionally to sell new phones. Apple has not responded to these allegations yet. Also Read: iPhone X Sales Below Company’s Expectations