Hello T. Gardener!
Steak them up for temporary support. Im guessing you didn't harden them off? So the additional stress of temperature acclimation, plus exposure to other elements, like wind and rain. Is to stressful for the new flimsy indoor plants, and the extra moisture on the plants, becomes to heavy for self support. So the tomatoes may need some steaking untill they adapt. Once steaked, you
should see drastic improvement in a few days, and new growth starting in about seven days, if the
roots weren't to stressed from transplant. Of
course thats assuming your outdoor temperatures and soil are adequate for optimal tomato growth.
Hope that helps.