I have a small computer repair shop. I've turned away numerous people wanting me to fix their cracked screen on their iphone & ipads. I've done a little research & am getting ready to buy some broken phones to practice replacing the screens & such before I actually do it on a customers phone. My question is, on an iPhone 4, is the screen bought seperate than the digitizer. And on the iPhone 5, is it all built into the screen (the LCD & glass)? I just want to make sure I'm stocking my shop with the correct spare items due to to the shippipng being outragous if I just order a few items...and what about the adhesive tape or glue...what do you recomend? Are the adhesive tapes different for each phone & iPad or can I just buy a big roll of it....thanks for any input as to this.