I finally bought in to the whole smart phone thing a couple of months ago and went with the Samsung Galaxy Express running ICS on ATT. I like it alot but would like to be able to customize a bit more than just using a new launcher (using Apex). Here are some of my questions:
1. In order to do more customization with regards to lockscreens and home screens (more info on the lockscreen and maybe a bit sexier, LOL), must I root the device to accomplish that?
2. If rooting voids my warranty, does it keep me from upgrading to the next OS (JB) when that becomes available for my phone?
3. Should an upgrade become available, who do I get it from....Samsung or ATT?

I know these are probably ridiculous questions to some but I was having a hard time weeding through so many other threads that I thought I'd post. Thanks in advance for any help.