On the back of iphone4, it says that it was designed by Apple in California.

On every Apple device, you can see "Designed by Apple in California", which is Apple's unique California design imprint. This symbol, which has been known to countless people for many years, was not registered until last year.

"Apple Design in California" has officially become a trademark.

Apple first submitted an application for trademark registration on 20 13 12.26, and also submitted an application in Europe, but there is no relevant news in Europe at present.