So I made this app for android:
https://play.google.com/store/apps/details?id=me.namaz.namazguide
What it does is that it will detect the sujood you do while praying, the number is shown on the screen and you should be able to see it. The purpose is the help those people who forget how many rakats they have completed, or are otherwise having difficulty concentrating during the namaz.
If you are interested, please post here so I can add you guys to the beta test program, so then you can download the app for free.
by the way there is also a free version of a similar app available on the store:
https://play.google.com/store/apps/details?id=com.jimyaghi.countingprayerrug
but perhaps you will buy mine instead and help future development.