The iPhone 4/4S LCD is a high resolution (640x960) LCD. (One of?) The manufacturer(s) is LG, where the panel goes by the designator LH350WS1. I’ve built a little breakout board which connects the display to a standard Altera HSMC connector. The design files (Eagle format) are available under a Creative Commons BY-NC-SA license. What that means is that the design files are free to use for any noncommercial purpose as long as proper attribution for their source is given. The VHDL will be available under a GPLv2 license.
The connector that is on the LCD itself is a JAE WP7-P026VA1. This is Digi-Key part number 670-2587-1-ND. The part that goes on this board is the socket, JAE WP7A-S026VA1. That is Digi-Key part number 670-2586-1-ND.
Update 20140414: I think I have this reversed. See #486.
Update 20150318: No, these connectors aren’t right. Right now I’m just ordering the iPhone 4 motherboard display connectors from the various vendors you can find online. JAE replied to my enquiry to say they absolutely do make the connector, that Panasonic is probably another vendor who makes them, but that they are under contract with Apple to not sell these customized connectors nor share any detailed information about them. You might be able to get the correct part from Avnet if you have an MFI contract in place. Sorry about the false hope.
The HSMC connector is a Samtec QTH-090-02-L-D-A. Digi-Key has it as part number SAM8194-ND. You can usually get a couple samples for free from Samtec directly. They’re a bit of a bugger to solder because they have a center ground rail which you can’t get at with an iron.
I realized too late that the TP622xx series of switching regulators don’t go up to 5V, and in fact their maximum input voltage is 6V. This kicked off a search for alternate parts (see #473) which led me to the discovery that the general footprint for a SOT23-5 regulator (switching and linear) are almost but not quite standardized, if only by convention. This means that I can technically substitute almost any LDO for the more expensive switcher as long as my power requirements are low, which I think they probably will be (we’re driving an LCD, not launching a rocket).
To that end, it looks like I’m going to bring in a few AP2210K-ADJ for stock.