Both YottaMark and FoodLogiq offer systems that let shoppers type a textcode into a mobile phone or home computer, or scan a bar-code using a phone's built-in camera, to find out when the tomatoes on the shelf were picked and which field they came from.
The source code for the existing Silent Text version is here and the company tells me that the new Silent Text source code will be released sometime in March or April after confirming legal issues such as licenses for third-party libraries.
If you have already created code for laying out labels according to the bottom or center point, your text will move around a little and you will need to adjust your constraints.