[bendyfoot]

Apples are totally fine and make a wonderful healthy treat. Tomatoes are fine too, but shouldn't be consumed in enormous quantities (like several pounds at a go). Both are great as components of a healthy diet. Try to avoid giving people food scraps if they're seasoned, salted, fried, fatty etc. A little yogurt or fresh fruit or veg or plain meat scraps wouldn't hurt, but be mindful that any extra snacks mean extra calories, and you don't want your pup to become unhealthily portly.

As far as the food change goes for you little cutie, there's absolutely no reason not to start it right away...why keep feeding her junk during these very important months of growth? Just do the transition gradually, over the course of 10 days or so. A simple rule of thumb to switch is "10%". Day one, feed 10% new food and 90% old, mixed together. The second day, feed 20% new food and 80% old food...and so on. For most dogs thats more than enough time to do a change that won't upset a potentially sensitive tummy.