In my application, I already have all the part of the user to take photo ready, but now the need arose of having in the photo taken, the date and the time it was taken, as a watermark, just as it happened in digital cameras Old.
Anyone ever had to do the same and could you give me a hand?
Try using following plugin. May solve your problem
So I understood this plugin, it gives the option pro user to edit the photo, but what I need is that the application itself after the photo is taken by the user, add this watermark with the date and time the photo was taken .
Basically the same behavior as this app has https://play.google.com/store/apps/details?id=com.jeyluta.timestampcamerafree
try using watermark.js file. A plain Javascript uses Canvas to add watermark to your image.
this works for me 
can you share the code or any references