I can’t use the zap feature it shows below image. I have blue wallet on my phone and it pops up automatically with this and no way to change it 
Discussion
Unfortunately we have no control on what app your device choses to open.. We wish Apple / Google let users select "default apps" for certain actions but they don't.
A workaround to this problem is to delete all the wallets you don't use so that the device is forced to open the right ones
Unfortunately we have no control over which apps your device opens. Our suggestions is to delete all the wallets you don’t use.
Some feedback. As iPhone users do not get a way to change default wallets you guys need to add a wallet chooser or a way to at least copy the invoice. This will allow iPhone users to use the zap function if they have an incompatible wallet such as blue wallet