In the end, this can only be answered by God, but we would like to ask all critics the following question: Are the prayers valid if you do not understand the meaning of your spoken words?
From our understanding, the core idea behind doing prayers regularly is to remind yourself of Gods words. That’s why it is very important to really understand what you’re saying during the prayer and not just to repeat some words in a foreign language in a beautiful sounding way. While that might give a spiritual feeling, it doesn’t fullfill the regular reminder role the prayers should have.
In Islam, things are always made simpler for those who have obstacles set in their way. God wants Islam to be accessible to all of us. That’s why we believe that reading more differing parts of the Quran from an iPad during prayers in a language you can understand is much better than speaking the same phrases you don’t understand over and over again.