Dates in a box, bananas, apples, oranges... The hardier things. And a big bottle of water.
I take bananas, dates, and those packs of three romaine hearts. I also take banana/green smoothies with me everywhere...in a water bottle or mason jar. And yes, always a big bottle of water.
Datorade travels really well I find. I have a little travel blender so I can take the cup from that with me when I go out for the day, either with datorade or a smoothie in it. Chopped fruit salad keeps well in either zip-seal bags or in a plastic pot, especially with an ice pack next to it. Dried figs and dates are always a good option, bottles of oj, little bags of greens, or just a bunch of bananas are all great for when you're out and about :) Have fun! Esperanza xxx