How mobile-friendly is Firefly?

Firefly provides an iOS app that is compatible with iPhone, iPod, and iPad.

For Firefly BonusLink members, you'll be able to manage your account from the app, though using their website will no doubt provide more functionality

The Android apps from Firefly work with all Android phones and tablets from various manufacturers (Samsung, LG, Google, etc.), and Android Wear watches might also be compatible. Perhaps standard practice these days, the Android app offers the same functionality as the iOS app from Firefly.

Also take a look at Firefly's website by clicking here — you should be able to do what you need there.