There are a lot of jobs I would pay for that can be done on mobile.
Albion silver - can be farmed normally as it's a fairly typical MMORPG. Probably most time consuming option though.
Can be played on PC or mobile(go to the website for Android/mobile install as it's not on app store)
Also it's a great game so you might actually get hooked. Not sure what else has tradeable currency or items as it's rare in mobile
Also - I play Rangers of Oblivion, perfect world mobile, Evertale, AxE(alliance x empire), sometimes darkness rises and some others.
If you're good at Ark:Survival Evolved I would pay for a character that's leveled/has a base on a decent server. I get distracted with side stuff and am not the best base builder. Also time consuming.
Fastest & Easiest Profit - You can make an Evertale account(they can be rerolled too)[Check my thread or PM me for info about game] and do the main offline story/ current event stages(the ones for SSR Hero/weapon give stones for each stage) until you get 2-3000 or more soul stones and do the 10x summons ONLY. Process can be done in 8-12 hours if you're good, less if you're lucky/good..Try to get SSR Heros(weapons are good too). Once soulstones are harder to get just save the account restore code somewhere and reroll(reinstall game + wipe cache). I'd pay anywhere from 1000 to 5000+ FG depending on the team/items you managed to get and how many SSR's. The game is VERY fun and you earn the currency by playing the game not repetive farming. I can give you a guide for best start & efficiancy.
If you're interested and will actually follow through let me know and I'll start getting some FG together. I don't log into JSP daily very much anymore so you can use my discord info in my sig to reach me reliably & get help with anything in game.