Do I need an account to use the free Proton VPN? No, you do not need an account. Just select the guest access option on Start to use it. You do not have to enter any personal information while using the guest account (or any other information for that matter).
What are the limitations of the guest account? There are a few limitations:
- The guest account is only available for Proton VPN for Android.
- Guest accounts are limited to one connection at a time.
- Only five servers in the countries Japan, Netherlands, Poland, Romania, and the US are available.
- Proton VPN picks the server automatically, usually the server with the best performance. You can use the "change server" option to switch servers, but this is time-limited.
- No premium features. You can't unblock streaming services, do not have options to use multi-hop connections, get no split-tunneling, may not use use the stealth protocol to bypass VPN blocks, use P2p, or the NetShield ad-blocker.
- Slower speeds. Free servers are designed to server large numbers of users. Speeds are relatively slow compared to Proton VPN's servers for paying customers.
Are there any other things worth knowing? Yes, you may see occasional ads for paid plans. The app may show a banner for NetShield, a security component. It does not impact functionality of the VPN and you can ignore these easily.
www.ghacks.net
I meant to use it without an account. 
