Best of Tests is a series of fairly standard intelligence tests. You're asked to figure out the pattern in a sequence of numbers, symbols, or both. You'll also test your memory by repeating a pattern of blocks you were just shown, or uncovering matching cards after you've been shown the layout once. A simple vocabulary game shows up as well, with questions like "Find the word that means the opposite of Near."
Best of Tests features only 3 main modes: Intelligence tests, Memory, and Training. Memory is just what it sounds like, featuring variations on remembering a picture or number and then on the next screen inputting what you're asked to recall. Intelligence is basically the "everything else" category. Training lets you go through the tests without a score being recorded, but it's pretty much identical to the rest of the game, so it feels a bit pointless. French and Spanish modes are also available if you would like your instructions in those languages.
After a while, although the questions are random, the tests repeat, and you don't necessarily have to spend time figuring out the "rules" to each question. This also means that things will start to feel very repetitious, very soon. Part of the draw of these kinds of games is the stimulation of being asked to think in new ways and stay mentally aware. But in Best of Tests, there are some tests where you can predict what you will be asked, so you will learn to automatically tune out extraneous information. For example, sometimes you're presented with a memory game where you are shown several objects. When you see a pair of matching objects in the group, you can be sure that the follow-up question will ask you to remember where the pair of matching objects were, so you'll learn to tune out all the other objects. Since there are so few varieties of tests included, it starts to be less of a test, and more of a chore after a while.