You only need a Peertube account – and the app, if required – if you’re a content creator and want to upload your own videos. You can watch videos without needing any account at all, either in your browser or on your mobile using an app, such as the Peertube app or NewPipe. SepiaSearch offers a comprehensive video search (covering a large number of selected instances).

If you want to subscribe to channels, watch, share or comment on videos in the Fediverse, you can do so from your Fediverse account, i.e. from Friendica, Mastodon, Sharkey, etc. You can also subscribe to Peertube channels and watch videos using your Lemmy account. I’m not sure, though, if all the features are available with Lemmy.

Zumindest wenn es nur um Verbindungsabfrage geht ist bahn.expert sowieso besser. Fahrkartenkauf usw. geht da allerdings nicht.