Solo play still needs an internet connection
Loftia is designed as a persistent online multiplayer world. The official FAQ says you can choose to play alone, that solo play will not block your progress, and that you can enjoy almost all of the content.
“Almost all” is not a promise that every activity can be completed alone. Solo also does not mean offline: an internet connection is required to play on every platform.
Playing on the same server
Players need to be on the same server to play together. The developer says you will not be locked to one server, so you can join your friends.
The reviewed information does not establish the exact server-selection screens, invitation sequence, party size, neighborhood-joining steps or matchmaking behavior. This page therefore explains the announced rule rather than providing a tested joining tutorial.
Player limits and private servers
A reliable current player-cap figure and a private-server option were not established in this research. Historical Beta player recollections are not a confirmed limit for the upcoming Demo or Early Access launch.
Cross-play also remains unpromised. Check platforms and support plans before assuming friends on different platforms can join each other.