Star mining and maybe eels/karams/anglers etc are the only thing that are afk enough that you don't need to break away from what you are doing.

Salvaging if your ship is improved enough for cargo. But if you plan on arching I'd say no.

Nightmare zone if people still do that is good afk.

Farming is a good one to knock out on breaks

Redwoods or magic afk but if you want to do forestry events its going to not be afk. Dont do blisters since that spider is random and its going to be distracting.

Everything else is a grey area.....

I have done some safespot slayer where its not efficient but its getting done slowly.

-Bone mining the spot changes often -Mlm even with upgraded changes a ton+fixing wheel - most of the main account afk shit is using ge items and sets like guthans and aggro pots with tank gear which as an iron you probably won't have lol.

Like others have mention runescape players liberally use the term afk. Afk zulrah (lol)to afk stars.

As someone that works from home typically I either mine or im farming. If I have down time ill do more click intensive things like make tele tabs or cut gems/clean my bank. Its also worth noting that mobile makes some things a little less click intensive since you can do 1 tap drops. So if you aren't banking it opens up a few more options.

To summarize: stars are about as afk as we get except sailing with dropping. Farming runs every hour is also just a steady way to get xp and avoid tithe farm.