You can download an Android emulator like Bluestacks and login to the store on it. Then you'll have a device attached to your account and can buy any compatible apps.
Be careful though, if the emulator is compatible with an app but your new Moto G isn't, you'll have wasted that money.
Thank you for the info. I'll try out and I don't know if there will be any app non compatible. Moto G comes with lastest Android version.