for iphone, damus. for android, amethyst. android has a much more interesting array of nostr centric applications including an appstore which uses ‘web of trust’.

web, when i do use it, coracle, the bizarrely named and wildly functional next.nostrudel.ninja

there is also the gossip desktop application written largely in rust i think. you might like this.

there is also ditto, by the guy who built soapbox for fedi. its a self hostable server which merges nostr and the fediverse (have never tried this)

there are also some interesting personal relay projects you might find interesting. haven is one, nostr-relay-proxy is another. start9 has alot of (theoretically) one click install options for self hosting. relays, lightning nodes, etc.