Yes, and no. If you're using the app on different devices on the same platform, and you're signed into the same account on each device, then your upgrades will be accessible across devices. For example, if you have the Hurricane Tracker upgrade unlocked on your iPhone, then that upgrade will be automatically unlocked on your other iOS devices, as long as you're signed into the App Store with the account used to purchase it. The same is true for Android to Android, Windows to Windows, etc. 

Allowing upgrades to transfer cross-platform presents a few difficulties: Microsoft, Apple, and Google, would each want a cut of every transaction, which would make it hard to keep up with development and up-time. It would also mean we would have to store sensitive customer information, which would put users' data at an unnecessary risk.