I also buy canned diced pineapple (in 100% juice, no sugar) and keep it in the pantry for fruit emergencies.

Oh, and after just seeing the title of another thread - watermelon, too!

Agree with melon, pineapple, strawberries (very ripe ones won't hold up well, but otherwise great), grapes, mango. I think other fruits that aren't very ripe would also do well for 1-3 days - plums, peaches, nectarines, halved blackberries and blueberries. Clementines probably too - peel and cut the section in half and store in the fridge. Cherries would work too, but they're a pain, period! My 17 month old can do whole raspberries now with no problem, so that's a good no-prep option (just rinse).

For diced raw veg, try zucchini (should stay fine for at least a couple days), and quartered grape tomatoes.

Melon ( cantaloupe and honeydew), apples, grapes, pineapple, firm strawberries and mangoes will be OK for a day or two. Tossing the cut apple with lemon juice will help prevent browning.

We are trying to incorporate more fresh fruits into our 17m old's diet but find we always run low on time to do the prep. I'd like to dice up some fruits/veg ahead of time but am not sure which ones would keep the best after being diced? Any suggestions?