Q: how can i use wallapop on my mac

Hi malcolm 168,
 

Thanks for contributing to the Apple Support Communities.
 

It looks like you want to download the iOS app Wallapop on your Mac.
 

Apps from the Mac App Store can run on your Mac (see Mac App Store: Frequently Asked Questions (FAQ)), but apps from the App Store in iTunes are meant to be used on iOS devices.
 

You can download apps to your computer and sync them to an iOS device (iPhone or iPad)--Sync your iPhone, iPad, or iPod touch with iTunes using USB. You can also download them using an iOS device--Download your past purchases.
 

All the best.