www.youtube.com In this video I show you how to write in all caps locks on the iphone. It can be done on the iphone #G, iPhone 3GS, iPhone 4, and iPhone 4s. All you have to do s double tap on the capitalize button and it will turn blue. They you can write in all caps without having to hit it again. Then to turn it off you just tap it once. Nice little trick if you need to write in caps lock.