Hello guy. I might need some help here. I rooted a few months ago but never flashed. Now I want to flash a ROM to try it out and I was reading some stuff in XDA Developers but I think I still don't get some things completely.
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1. As far as I understand it, ENG-Off is needed to install a radio using a command prompt and adb on your desktop. It also opens you up to make other modifications that, if you don't know exactly what you're doing, can really mess up your phone (permabrick). There is an easier and safer way to flash a radio that does not require ENG-Off. Read this thread and understand it before attempting to flash a radio.
[RADIO][ADV]Inspire Radio how to without ENG S-OFF
You don't NEED to flash the recommended radio when using a custom ROM. However you may get better performance because the RIL for the recommended radio is cooked into the ROM by the dev. Supposedly an unmatched Radio/RIL combination can cause some performance issues, including faster battery drain. You may want to try running the ROM w/ the radio you currently have for a while and see how it performs. Or just flash the RIL for the radio you currently have. That's what I did. I'm still running the stock radio, flashed its RIL into my ROM and it runs great. If you're not happy with the performance with that, then try flashing the recommended radio. However, if you flashed an RIL, you would then need to flash the RIL of the recommended radio as well.
2. ClockworkMod Recovery (or some other recovery application) is required to flash custom ROMs and mods. It also allows you to backup your existing ROM (a nandroid) and to restore your ROM backups.It's easy to install using the ROM Manager app. I recommend reading this article to get a deeper understanding of what CWM is and how to use it.
What Is ClockworkMod Recovery And How To Use It On Android
3. If you get all your apps from the Android Market they should all still be available to you. They may not all immediately be pushed to the phone when you install a new ROM. But you can go to the Market website and install them from there. If you have paid apps those will also still be available. If you got any apps from Amazon you would need to first install the Amazon App Store app. Then log in and it will give you the list of apps you've purchased and you can install each from there, including any FAOTD that your got.
You can use Titanium Backup to back up and restore your apps and data. However I would refrain from restoring system apps and data. Sometimes they are not compatible with the custom ROM. You could end up getting a lot of force closes.
You can also use ES File Explorer, Root Explorer or Astro File Manager to backup the apks of the apps you currently have installed. It will save the apk to your sd card and you would use the file manager app to reinstall those. However that doesn't restore any user data (eg. game progress).
As for ARHD, it's a great ROM. I've been running it for a few weeks and love it. Make sure you download and run the Super Wipe script before you flash the ROM. When you do, it will replace CWM with 4EXT Recovery. Don't worry about that. 4EXT works great as does its Control app. I actually like it better than CWM/ROM Manager....The ARHD dev just released a new version yesterday, 6.2.0. So you may want to wait a few days to see if any bug issues are reported.
4. You should also make sure your contacts are sync'd to Google. Once you install the ROM and sign in to Google it will automatically sync your contacts/calendar/mail. If you have any contacts stored on the phone, you will want to back up those to your sd card. Also be aware that you'll most likely lose all your SMS & MMS unless you use an app to back those up. GO SMS allows B&R of SMS but not MMS. I'm sure there are others. You can also try using TiBackup to backup
[SMS/MMS/APN] Dialer Storage, which would back up everything, however since ARHD uses a different base than the stock ROM, it may not restore.
I know there is a lot to figure out the first time you do it, but once you do, you'll realize it's not as daunting as it sounds. Just read until you understand as much as you can and then go for it. And ALWAYS backup your current ROM.