UK/London Bus Apps

Hi, can anyone suggest a replacement Bus App for me as my favoured London Bus app apparently will not work with IOS11. I ham trying out Traveline GB and Bus Checker but nither of these are consistant in finding the nearest stops to me.
I suspect I may be missing something so if anyone has experience with these 2 alternatives can they advise me on how to focus them to find the nearest stops to where ever I may be at the time.
Thanks in advance.
Mark