This smart touch I like the many in Flyme 5 in Flyme 4 was no so beautifully designed and had errors in use but Flyme 5 is great I have no words for this smart touch I like the many Flyme OS, always near our thumb and should not bend to the bottom of the phone to touch on mBack.
   With this option we have a bigger screen to use unlike other OS which have reduced screen while using the additional buttons for back, please hold the smart touch in the future in Flyme OS 6 .