Adding a Git hook to our CI process is one of the approaches we are exploring. However we are keeping it manual for know just in case somebody edits the script with a wrong string, we would like a human to take a look at it before it gets pushed.
As for the string differences: We like to design our interfaces so they feel at home on the platforms. This means that sometimes some labels are visible on one platform and not on the other. Also, iOS and Android formatting might differ, and one string might be split into two due to the differences in iOS and Android UI frameworks.
These are usually edge cases and are pretty obvious in the script, so we didn’t have any issues with this. :)