So I'm a jailbreaking newb. I am on 4.2.1
What do I do because I am tired of not having custom text tones
Jason - if all you're wanting is custom text-tones - that is, to be able to assign a different tone to a contact, upgrading to the latest iOS will get you that feature. In the last couple releases of iOS, 4.3.2 included - per contact, one can assign a "Custom Ring Tone" and "Custom SMS Tone".
But if you want even more flexibility, more tones, assign tones to different apps, etc., then jailbreaking is the way to go.
Since you're already on 4.2.1, I would download
Greenpois0n and use that to jailbreak your device. Here's a walk-thru on how to jailbreak 4.2.1 with Greenpois0n:
How to Use GreenPois0n Untethered iOS 4.2 Jailbreak (Guide) - iSmashPhone iPhone Blog
As with any upgrade, major change: make sure you backup your device first; sync it in iTunes, make sure you're syncing your music, apps, etc.
One thing to note with jailbreaking is that you DO NOT want to just upgrade to the 'latest and greatest' iOS - the jailbreak will likely not be there. That said, the latest iOS 4.3.2 does have a jailbreak out, but it's a little more involved.
I would start with jailbreaking your existing 4.2.1 and play with it. Once jailbroken, you'll see an icon for Cydia; this is where you'll download all the cool apps/themes/ringtones/sms tones, etc. that make jailbreaking worth it!
Make sure you download:
- SBSettings - puts commonly access settings available with just a swipe of the status bar (free)
- Winterboard - the prevalent theming engine for jailbroken iPhones (free) Once Winterboard is installed, you can search Cydia for themes, ringtones, SMS tones and install them. (Some stuff is free, some costs $$)
- ToneFXs or MyProfiles - either one of these apps will allow you to REALLY customize what you do with your tones. (both cost $$)
- BiteSMS - the best text messaging app out there! Emoticons, templates, you name it - if you do a lot of texting, it's a must-have. (costs $$)
- MyWi - lets you tether your laptop and other devices to your iPhone to access the Internet
- FiveIconDock - allows 5 icons in the dock instead of the default 4 (free)
- Backgrounder - More robust backgrounding of apps - including those that don't natively support backgrounding (free)
- MultiFl0w - Great multi-tasking switcher (costs $$); requires Backgrounder
- Activator - allows one to assign gestures and functions (button push) to apps and system actions (free)
- OpenNotifier - puts icons in the status bar for different events (missed call, email, sms, etc.)
- AptBackup - to backup the Cydia packages that you have installed (for when you upgrade, it will help reinstall what you've already downloaded) (free)
- PkgBackup - Does the backups also, but much more robust - can upload the backups to DropBox, Facebook, email, etc. (costs $$)
- PwnTunes - Let's you upload/download music to your iPhone (costs $$)
- FastSnap - Let's you take a picture by pushing the volume buttons, as well as the 'on screen' button. (costs $$)
- PowerPlay - Let's you control the iPod music player with the volume buttons - even when the device is locked - VERY handy! (costs $$)
Anyway, that's just a very short list of the cool stuff and handy apps. Once you get started with a jailbreaking - you'll wonder how you managed without it!