What is Mastodon?
https://youtu.be/IPSbNdBmWKE
What to use an app to access this server? Try these:
iOS: https://apps.apple.com/us/app/mastodon-for-iphone/id1571998974
Android: https://play.google.com/store/apps/details?id=com.keylesspalace.tusky
Or you can just acess from a web browser (Chome or Safari) and create a bookmark.
@Mich
“Home” : Is your personal feed, it show the posts from the people you follow.
“Local” : Is the feed that shows all the posts from this server / instance (sarnia.lambton.social)
“Federated” : Is the feed show all the posts from all the servers / instances this server is connected to.