re:
Welcome to Windows Central.
The seemingly highest priced Windows Phone app I've seen so far that is still published is
Dark Diamond, currently priced at $94.99. Not sure about the second highest priced app, but here's
CoPilot Europe, priced at $49.99.
I'm also not sure about the average price of
paid windows phone apps, but according to sources it was somewhere at $3.96 in 2012 (for WP7), $3.49 in 2013 (WP8)... so with non-linear asymptotic ($0.99 lower limit) extrapolation to 2014-2015, it should be somewhere near $3 by now.
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