[EVO 4G Q&A, Help & Troubleshooting] Shidell:
It seems there is a lot of questions regarding the EVO, root and more--so in an effort to clean up redundancy, I'll make an attempt to answer many questions in this thread. I'll touch on a number of important points initially, then you can fire away with questions which I'll (do my best) to answer.

If you have a question, you should read this thread before asking, as it may very well be answered here. If you don't see it, ask away!

Is the EVO GSM-compatible? Can I use it with Verizon?

Short answer: No. The EVO is CDMA-only, and does not contain a SIM card slot. You can try to get Verizon to accept the EVO on their network, but doing so will require you to first convince a representative to do so, which has been virtually unheard of (Sprint and Verizon, despite using the same CDMA technology, maintain HEX ID white lists for phones, and if your phone doesn't match, they can't activate it in their system.)

If you're on Verizon, I'd advise you to consider the Incredible, or wait for the Shadow.

What is 'Root'?

Root access (in linux/unix terms) is the equivalent of being an Administrator in Windows. Without being 'Root', or 'Administrator', what you can and cannot do is severely hampered. You are essentially using a 'Guest' account, with 'Guest' priveledges. This means that whatever HTC/Sprint/Etc. has deemed appropriate for 'Guest' users is all you have access to.

So why do I (or we) want Root access?

Having Root access means we can do whatever we please to our phones. As I said above, this gives us Administrator rights to add, delete, or do as we please to our devices. Without Root, you are forced to do (and use) whatever software Sprint/HTC want you to use.

Can you give us some examples?

Yes. With Root, you can flash a build of Android that someone else has created and/or customized. You can update/reskin your device as you please, add or remove software at your liking, and tether free of Sprint's surcharge. Additionally, without Root, you'll have to wait for Sprint and HTC to release updates for the EVO (which could be months..) with Root, you can load a build as the developers produce it.

Froyo will most certainly arrive (in time), but what about Gingerbread (2.3)? Whatever comes after (2.4)? There is no guarantee that Sprint and HTC will support the EVO that far out. The developers who have this phone, however, most certainly will.

I'm going to have my EVO for at least two years, and I plan on migrating and updating my device to the latest version of Android regardless of what other customers/users who do not have Root access are able to do.

...But there's a risk in getting Root, right?

Yes, there's a risk of bricking your phone, and however minimal that risk is, it needs to be stated. Your best friend is knowledge, so read carefully, read again, and follow directions. You're already here on XDA, you'll be just fine.

I'm concerned that the developer's builds of Android Eclair 2.1 and/or Froyo aren't fully functional, or we won't have the same functionality after Rooting.

Patience. :) Functionality is dependent on having a Kernel that supports all the technology on the device; an OS to run with that Kernel that supports all of the technology on the device, and the device itself. We have the device and the Kernel, we're just waiting on an official AOSP Froyo release.

If that doesn't make sense, consider this: HTC heavily modified Eclair to support technology like tethering, 4G, front and rear cameras, HDMI, etc. They had to modify it manually because support for it wasn't available in Eclair, but it IS available in Froyo.

In time, everything on the EVO will be fully functional in Froyo.

Where's Froyo?

Google will make Froyo available on AOSP when prepared to do so. Until then, the latest release of Android is Eclair 2.1r1. Again, Eclair doesn't support everything the EVO has to offer, so until Froyo is available, some items may not come to fruition in the developer community (4G access, tethering, etc. as examples.)

Wait a minute, can't I run Froyo from an SDK build? :confused:

Yes, you can--but an SDK (Software Development Kit) build is essentially OS files torn from the emulator in the SDK. This may or may not contain all of Froyo's end-result code, and may not be completely indicative of what a final release of Froyo will be like. It IS very useful for testing and tinkering, and isn't necessarily even a bad build to use on a day-to-day basis, as long as you understand it's limitations. When you're reading threads about functionality for a Froyo SDK build for the EVO, now you'll hopefully have a better idea as to why that functionality is limited right now.

I hate Sense UI! What can I do? Can we remove it? Can we replace the modified applications?

You can disable Sense, but you can't remove it (unless you're Root and can replace the OS entirely, that is.) Sense is deeply integrated into the core of Android in the release HTC and Sprint provide, so much so that certain applications (People, Messages, Internet) cannot be "undone" short of (again) replacing the ROM. You can disable the widgets, and replace the launcher (ADW Launcher is a solid alternative), but at the end of the day, Sense is so tightly coupled with the EVO stock ROM that you can't completely remove/replace or restore the original Android system files.

This is another good argument for wanting Root access.