Ok the problem seems to be that I don't know if I have added the app to root of the device. I made on my sd card map with name Navi. In this map there is navi.apk and other files (data, ect.). I have inserted the sd card into the map slot on the device. After this I press on navigation icon and it offers zo install the app. According to you this procedure is NOK. So how can I add this to the root of my device?
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