https://www.theguardian.com/technology/2017/oct/09/apple-slowing-down-old-iphone-data-iphone-5s-iphone-6-iphone-6-iphone-7-ios-updates

Data shows consistent performance for iPhone 5S, iPhone 6, iPhone 6S and iPhone 7 with successive iOS updates, but that doesn’t mean the phones don’t feel slower

It’s a perennial question asked in offices, pubs, shops and across the internet every year in the run up to the launch of a new iPhone: does Apple slow down older iPhones to make you buy new ones.