Started using for my iphone 13 - after built in camera lagged too many times I am happy to have downloaded this so long ago (iPhone 4 maybe?) - it was helpful here and there but once the built in camera app starting lagging ( unable to take a picture less than 5-6 seconds after opening, pictures are captured almost a full second after the shutter button is pushed ) - this app replaced it and has become both dependable and essential.