secrec
Because there is no REASON for them to distribute their own software unless they're sneaking something into it. Why go to the trouble when you can just say "use wireguard, here's the config for it"?
To be clear, I'm not saying that they ARE sneaking something into it, just that its suspicious that they would bother making their own software.
There's plenty of reasons why people could want a ProtonVPN app over a manual list of their Wireguard configs:
- Fastest server to your current location and network conditions
- Finding servers with a lower current load
- Getting real-time server list updates in case of outages or IP changes
- Easier split-tunneling (setting in 1 place vs each config)
- Supports multiple protocols in one app (Wireguard, OpenVPN, IKEv2, their own censorship-resistant "Stealth"protocol)
- Cool world map UI
For example, I use manual Wireguard configs on my router and to get updates, I run a long combined curl and jq command on my laptop to get a table of the node-id/country/city/IP/pubkey/load/features-bitmask. This also requires a valid token for the API call which is a pain to get. But this is all less work than using the website to get the same info. This would be an absolute nightmare to do on mobile.
Healthy skepticism is good, but it should be balanced with possible motives, their likelihood, and attempts to verify or refute the claims. You might could try to inspect all the app's network traffic (dunno if you can proxy any of the TLS connections - certs might be pinned, might could decompile and swap em) or dump memory for any other clues.