Have you tried to attach your Myki card to your smartphone? Nice try; however, it won't work because strong electromagnetic fields from your smartphone disturbs communication between your Myki and readers.
Why don't you try with T-Plus EMF shield and specialised case for Myki card?
It is very simple to install and you don't need to take out Myki card from your wallet anymore.
Simply touch on and off your iPhone in bus, train or tram!