What you need to know about Garuda Indonesia mobile apps
Like many other airlines, Garuda Indonesia offers an iOS app for all of your Apple devices.
For Garuda Indonesia Garuda Miles members, you'll be able to manage your account from the app, though using their website will no doubt provide more functionality
As the most popular mobile platform in the world, Garuda Indonesia has taken notice of Android and provided an app for most Android devices. Perhaps standard practice these days, the Android app offers the same functionality as the iOS app from Garuda Indonesia.
Also take a look at Garuda Indonesia's website by clicking here — you should be able to do what you need there.