This is a phone that costs with sales taxes, over $1000. At one point, it was so slow that I felt like throwing it on the wall, and breaking it into a thousand small pieces. (There even was a lag between me typing on the on-screen keyboard and those characters appearing.) I replaced the battery (about a year ago), and the speed improved a bit, but not completely.
I had to get a new phone because it was (still was) simply just too slow. Honestly, there needs to be some sort of class-action lawsuit and compensation for iPhone owners who have literally been swindled by this.