Questions: EU, iOS, Waterproofing

[AkshayRao27]

Hi there! We're planning on getting a dog this year and I've been looking all over for a subscription-free GPS tracking solution, which is how I stumbled upon this project. I'm considering giving it a shot but before I start, I have a few questions:

1. I'm in Austria. The Hologram website quotes €25 for shipping the SIM card here. Before I actually pay for it, is there a way to get one of these SIMs for a shipping cost that's more... reasonable... compared to the price of the SIM?
2. Is an iPhone absolutely essential to work with the device or is there any way around the iOS requirement?
   None of us at home have any Apple devices, and no one in my family or in my friend-circle has an iPhone. It'd be excellent if I don't need to procure an iPhone from somewhere just for this one single purpose...
3. Is there any way to make a waterproof 3D printed enclosure? Since I intend to use this for our dog and since our dog will very likely go swimming with us every summer, I'd like to somehow waterproof the enclosure. Does anyone have any experience here that they can talk about?