Surf weaves Mastodon, Threads, Bluesky, RSS feeds, podcasts, and YouTube into something that wouldn’t have been possible until recently. Fourteen years ago, when the iPad was new and bursting with unfulfilled promise, an app called Flipboard debuted. Billing itself as a “social magazine,” it let you sign in with your Twitter and Facebook accounts and then browse your feeds in a beautifully designed environment that instantly became a showcase for Apple’s tablet.