Some of my other tomato plants are growing quite well also, like this Zapotec. I temporarily stuck a stick in the pot to keep it upright but I really need to build a proper stake and support system. I find that with large tomatoes in containers a single large stake is not enough to keep the plant upright no matter how big the stake is. You can only push it so far into the soil.
None of my plants, except the black cherry tomatoes, have reached a height where they desperately need support. Still, I need to start planning.