II picked up a dev edition in dec, Which I have replaced with a retail. I'm still learning how to best use all the features. Like i just learned how to use the Pen Window today.
I also found a Sansung translation app for written and speech. Was having a blast with this and a Spanish speaking friend. He was speaking to his relative that knew very little English. Well he would start speaking in Spanish to his relative then started steering the conversation to saying stuff about me. He signaled to start recording at one point. When his relative responded he signaled stop, then i played it back in English for me. Well i put on a "shocked face" at what was said, then preceded to record and "Angry" response back and have the translator cuse him out in Spanish.
Vudu - Allows me to easily access and watch my collection if I happen to be stuck with nothing to do away. The larger screen also make it more enjoyable.
Music - I love the Adapt Sound. I believe also on the S4. It's basically a hearing test built into the phone, that adjusts the audio after it is complete specifically for your headset and ears. Makes my music on the phone a lot nicer to listen to.
Also helps to have a large collection to rotate through.
Remote control for LG TVs - I can control the TV using the phone and not have to reach for or look for the remote.
Oh and it can take a snapshot of what's on the screen ATM. Great for sharing stuff with family & friends.
TiVo Remote - Manage most features of my TiVo without having to move into the menus on the TV.
Next launcher. Allows me to change the look occasionally.