Protomaps makes hosting maps pretty cheap for open streetmap vector tiles. Most of the cost is actually the CDN bandwidth. It's not going to be nothing dependin

Protomaps makes hosting maps pretty cheap for open streetmap vector tiles. Most of the cost is actually the CDN bandwidth. It's not going to be nothing depending on the number of users but it shouldn't break the bank for Apple and probably is relatively low to other content they distribute (e.g. Apple TV) or OS updates. The way protomaps does this is by serving a single large file with all the map data via bucket storage and then using lambda functions + CDNs to extract tiles from there on demand. So, they don't pre-calculate the tile files and this simplifies the update process to replacing a single file. The CDN caches the extracted tiles so this is relatively cheap and doable even for small startups. So, this minimizes compute and storage. Generating the map tiles requires a bit of compute obviously but it's a constant overhead; and they have to do this anyway for their native apps. Probably the hardest part for them was building a hardware accelerated render engine for the web. Similar to Maplibre, Google Maps, etc. That would explain why it doesn't work on Firefox as well. And obviously Safari is a bit lagging with things like web GPU and WASM that I imagine would be useful for this.